Electrochemical synthesis method of 3-aryl quinoxaline ketone compound

Abstract

The invention discloses an efficient C-H arylation reaction between a quinoxaline ketone compound and aryl triazene, wherein the efficient C-H arylation reaction is induced by ionic liquid. In particular to an electrochemical synthesis method of a 3-aryl quinoxaline ketone compound, aryl triazene is used as a stable arylation reagent, and ionic liquid is used as an accelerant and electrolyte. Under mild, metal-free and oxidant-free conditions, the method can be used for synthesizing various 3-aryl quinoxaline ketone compounds and arylated quinoxaline compounds at medium to excellent yields. The scheme has the remarkable characteristics of being simple and convenient to operate, excellent in functional group tolerance, high in selectivity, high in product derivatization, suitable for gram-level continuous flow chemical synthesis and the like.

Description

Technical Field

[0001] The invention belongs to the field of preparing quinoxalinone compounds and discloses an electrochemical synthesis method of 3-arylquinoxalinone compounds. Aryl triazene is used as a convenient, stable and cheap aromatic source to undergo arylation reaction with a biologically active quinoxalinone compound under electrochemical conditions. Background Art

[0002] Substituted quinoxalone compounds, especially arylated quinoxalone compounds, are a class of molecules with broad biological activity and are widely used in drugs, natural products and materials. For example, the key skeletons of STK33 inhibitors, FXa coagulation inhibitors, and CFTR activators 4 all have 3-arylquinoxalone structural scaffolds. Therefore, great progress has been made in the synthesis of the above compounds. ( M.;Spoonamore,J.;Wei,J.;Guichard,B.;Ross,N.T.;Masson,K.;Silkworth,W.;Dandapani,S.;Palmer,M.;Scherer,C.A.;et al.A potent andselective quinoxalinone-based STK33 inhibitor does not show syntheticlethality in KRAS-dependent cells.[J].ACS Med.Chem.Lett.2012,3,1034-1038.,Willardsen,J.A.;Dudley,D.A.;Cody,W.L.;Chi,L.;McClanahan,T.B.;Mertz,T.E.;Potoczak,R.E.;Narasimhan,L.S.;Holland,D.R.;Rapundalo,S.T.;et al.Design,synthesis,and biological activity of potent and selective inhibitors of bloodcoagulation factor xa.[J].J.Med.Chem.2004,47,4089-4099.,Cil,O.;Phuan,P.-W.;Lee,S.;Tan,J.;Haggie,P.M.;Levin,M.H.;Sun,L.;Thiagarajah,J.R.;Ma,T.;Verkman,A.S.CFTR activator increases intestinal fluid secretion and normalizes stooloutput in a mouse model of constipation.[J].Cell.Mol.Gastroenterol.Hepatol.2016,2,317-327.)

[0003] In recent years, 3-arylquinoxalinones have been synthesized using different arylating agents such as arylboronic acid, arylhydrazine, diaryliodonium salt, arylamine, aryldiazonium salt, aryltriazene, diarylformyl peroxide, simple aromatic hydrocarbons, etc. Although there are many different arylating agents for the direct arylation of quinoxalinones, their low reactivity, limited substrates, poor stability and other disadvantages still restrict their application. Therefore, the development of efficient arylating agents with good stability and reactivity is still an urgent need. In recent years, the research on the synthesis of 3-aryl substituted quinoxalinones has achieved a series of excellent results.

[0004] ( A.; Brion, JD; Alami, M.; Messaoudi, S.Assisted tandem palladium(II) / palladium(0)-catalyzed C-and N-arylations of quinoxalin-2(1H)-ones inwater.[J].Adv.Synth.Catal.2014,356,3821-3830.,Bao,H.;Lin,Z.;Jin,M.;Zhang,H.;Xu,J.;Chen,B.;Li,W.Visible-light-induced CH arylation of quinoxalin-2(1H)-ones in H 2 O.[J].Tetrahedron Lett.2021,66152841., A.;Brion,J.D.;Messaoudi,S.;Alami,M.Palladium(II)-catalyzed qxidativearylation of quinoxalin-2(1H)-ones with.arylboronicacids[J].Org.Lett.2013,15,5606-5069.,Tian,M.;Liu,S.;Bu,X.;Yu,J.;Yang,X.Covalent organic frameworks:asustainable photocatalyst towardvisible-light-accelerated C3 arylation and alkylation of quinoxalin-2(1H)-ones.[J].Chem.Eur.J.2020,26,369-373.,Paul,S.;Ha,J.H.;Park,G.E.;Lee,Y.R.Transition metal-free iodosobenzene-promoted direct oxidative 3-arylationof quinoxalin-2(1H)-ones with arylhydrazines.[J].Adv.Synth.Catal.2017,359,1515-1521.,Song,S.;Shi,X.;Zhu,Y.;Ren,Q.;Zhou,P.;Zhou,J.;Li,J.Electrochemicaloxidative C–H arylation of quinoxalin(on)es with arylhydrazinehydrochloridesunder mild conditions.[J].J.Org.Chem.2022,87,4764-4776.,Samanta,R.K.;Meher,P.;Murarka,S.Visible light photoredox-catalyzed direct C–H arylation ofquinoxalin-2(1H)-ones with diaryliodonium salts.[J].J.Org.Chem.2022,87,10947-10957.,Yin,K.;Zhang,R.Transition-metal-free direct C–H arylation ofquinoxalin-2(1H)-ones with diaryliodonium salts at room temperature.[J].Org.Lett.2017,19,1530-1533.,Yuan,J.;Liu,S.;Qu,L.Transition metal-free directC-3arylation of quinoxalin-2(1H)-ones with arylamines under mild conditions.[J].Adv.Synth.Catal.2017,359,4197-4207.,Jiang,Y.y.;Dou,G.y.;Zhang,L.s.;Xu,K.;Little,R.D.;Zeng,C.c.Electrochemical cross-coupling of C(sp. 2)-H witharyldiazonium salts via a paired electrolysis:an alternative to visible lightphotoredox-based approach.[J].Adv.Synth.Catal.2019,361,5170-5175.,Kwon,S.J.;Jung,H.I.;Kim,D.Y.Visible light photoredox-catalyzed arylation of quinoxalin-2(1H)-ones with aryldiazonium salts.[J].ChemistrySelect 2018,3,5824-5827.,Wang,P.;Yang,Z.;Wang,Z.;Xu,C.;Huang,L.;Wang,S.;Zhang,H.;Lei,A.Electrochemicalarylation of electron-deficient arenes through reductive activation.[J].Angew.Chem.Int.Ed.2019,58,15747-15751.,Wang,B.;Feng,Y.;Zhang,Y.;Wang,S.;Zhou,X.;Chen,Z.;Xia,Y.;Jin,W.;Iqbal,A.;Liu,C.;Zhang,Y.Photo-driven direct C-Harylation of quinoxalin-2(1H)-ones with aryltriazenes under catalyst-free andambient conditions.[J].Eur.J.Org.Chem.2023,26e202300044.,Xu,J.;Zhang,H.;Zhao,J.;Ni,Z.;Zhang,P.;Shi,B.-F.;Li,W.Photocatalyst-,metal-and additive-free,direct C–H arylation of quinoxalin-2(1H)-ones with aryl acyl peroxidesinduced by visible light.[J].Org.Chem.Front.2020,7,4031-4042.,Xie,L.-Y.;Peng,S.;Yang,L.-H.; Peng, C.; Lin, Y.-W.; Yu, Chem.2021,23,374-378.,Paul,S.;Khanal,HD;Clinton,CD;Kim,SH;Lee,YRPd(TFA). 2 -catalyzed direct arylation ofquinoxalinones with arenes.[J].Org.Chem.Front.2019,6,231-235.).

[0005] In arylation reactions, aryl triazenes are often used as substitutes for aryl diazonium salts and are widely used to construct C-C bonds and carbon-heteroatom bonds. 3 ·Et 2 O,AgOAc,CuCl 2 ,Cu(OAc) 2 etc.) or Bronsted acid (HBF 4 , TFA, HCl, HBr, etc.) will generate aryl cations or obtain aryl radicals through further single-electron reduction. Based on this, in the present invention, we report that bifunctional ionic liquids catalyze aryl triazenes to produce aryl radicals, and complete the construction of 3 arylquinoxalinone compounds under mild conditions. The reaction raw materials are simple and easy to obtain, the substrate range is wide, and no additional ligands are required. Summary of the invention

[0006] The purpose of the present invention is to provide an aryl triazene as a simple and readily available arylation agent, in which an ionic liquid is used as an electrolyte and a promoter, and the arylation of a quinoxalinone compound is achieved without the need for the addition of an additional acid, and a 3-aryl quinoxalinone compound is synthesized. The advantages of the present invention include: ionic liquid promotion, cheap and readily available raw materials, a wide range of substrates, large-scale preparation, no need for the addition of an acid, and mild reaction conditions. In order to achieve the above purpose, the technical scheme of the present invention is as follows:

[0007] Under the conditions promoted by ionic liquid, quinoxalinone compound 1 reacts with aryl triazene 2 under certain conditions (reaction formula 1). After the reaction, the product is separated and characterized by conventional separation and purification methods to obtain the corresponding 3-arylquinoxalinone compound and arylated quinoxaline compound 3.

[0008] The structural formula 3 of the 3-arylquinoxalinone compound and the arylated quinoxaline compound is as follows:

[0009]

[0010] R 1 is one or more of H, methyl, chlorine or bromine, the number of which is 1-3; R 2 R is one or more of H, methyl, methoxy, ethyl, tert-butyl, n-dodecyl, halogen, C2-C6 ester group, benzyl, 4-methyldiphenyl ether and 4-methoxydiphenyl ether substituents, and naphthalene ring, and halogen is one or more of fluorine, chlorine, bromine, and iodine; 3 is one or more of methyl, H, ethyl, propyl, allyl, propargyl, cyclopropyl, cyclohexyl, C2-C6 ester group and benzoyl; "O / R 4 " stands for "O or R 4 "One or more of the following, R 4 is one or more of methyl, amino, and mercapto groups; the dotted line (dashed and solid lines) inside the benzene ring indicates that under different substituent conditions, that position can be a double bond or a single bond, such as R 4 Methyl, amino and thiol groups are single bonds (corresponding to O / R 4 The two lines between the benzene ring and the solid and dashed lines represent the position that can be a double bond or a single bond. In this case, this position is a single bond). O / R 4 When it is a carbonyl group O, it is a single bond, and that position is double bonded to the oxygen group.

[0011] A quinoxalinone compound 1 and an aryl triazene 2 are reacted in the presence of a bifunctional ionic liquid; after the reaction is completed, the products are separated to obtain 3 arylquinoxalinone compounds and an arylated quinoxaline compound 3.

[0012]

[0013] The substituent R 1 , R 2 , R 3 and R 4 Same as above;

[0014] When N-methylquinoxalinone 1 reacts with aryl triazene 2, the solvent is one or more of methanol, ethanol, acetonitrile, N,N-dimethylformamide, trifluoroethanol, dimethyl sulfoxide, dimethyl sulfoxide and acetonitrile (volume ratio is 1:0.5-2). The best effect is achieved when the reaction solvent is dimethyl sulfoxide. The amount of solvent added is 3-5 mL of solvent per 0.2 mmol of N-methylquinoxalinone 1.

[0015] When N-methylquinoxalinone 1 reacts with aryl triazene 2, the reaction is added with any one or two of 1,3-bis-butylsulfonic acid imidazolate acidic ionic liquid IL1 and 1-ethyl-3-butylsulfonic acid imidazolate acidic ionic liquid IL2, which is used as the electrolyte and promoter of the reaction, and the addition amount is 0.3-0.4 mmol of ionic liquid per 0.2 mmol of N-methylquinoxalinone 1. The preparation method according to claim 1 is characterized in that: the reaction current is one or two of 4-7 mA, and the best effect is achieved when the reaction current is 6-8 mA.

[0016] When N-methylquinoxalinone 1 reacts with aryl triazene 2, the molar ratio of N-methylquinoxalinone 1 to aryl triazene 2 is in the range of 1:2.5-1, and the optimal ratio is 1:2-3. When quinoxalinone 1 reacts with aryl triazene 2, the reaction time is 2-7 h, and the optimal reaction time is 3-5 h. The synthesis reaction of the present invention comprises the following steps: Synthesis of p-methyl triazene 2a:

[0017]

[0018] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-methylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 1 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be shown in 2a in the above reaction formula.

[0019] Synthesis of phenyltriazene 2b:

[0020]

[0021] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), aniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2b in the above reaction formula.

[0022] Synthesis of o-methyltriazene 2c:

[0023]

[0024] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), o-methylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2c in the above reaction formula.

[0025] Synthesis of m-methyltriazene 2d:

[0026]

[0027] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-methylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2d in the above reaction formula.

[0028] Synthesis of p-ethyltriazene 2e:

[0029]

[0030] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-ethylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be shown in 2e in the above reaction formula.

[0031] Synthesis of tert-butyltriazene 2f:

[0032]

[0033] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-tert-butylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2f in the above reaction formula.

[0034] Synthesis of 4-dodecyltriazene 2g:

[0035]

[0036] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 4-dodecylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2g in the above reaction formula.

[0037] Synthesis of p-methoxytriazene 2h:

[0038]

[0039] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-methoxyaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2h in the above reaction formula.

[0040] Synthesis of p-fluorotriazene 2i:

[0041]

[0042] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-Fluoroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be shown in 2i in the above reaction formula.

[0043] Synthesis of p-chlorotriazene 2j:

[0044]

[0045] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-chloroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2j in the above reaction formula.

[0046] Synthesis of p-bromotriazene 2k:

[0047]

[0048] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-bromoaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2k in the above reaction formula.

[0049] Synthesis of p-iodotriazene 2l:

[0050]

[0051] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-iodoaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 21 in the above reaction formula.

[0052] Synthesis of m-fluorotriazene 2m:

[0053]

[0054] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-fluoroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2m in the above reaction formula.

[0055] Synthesis of m-chlorotriazene 2n:

[0056]

[0057] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-chloroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be shown as 2n in the above reaction formula.

[0058] Synthesis of bromotriazene 2o:

[0059]

[0060] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-bromoaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was stirred in an ice bath for about 15 minutes, and then added into a 0-2°C solution containing 10 mL of potassium carbonate (1.2 mol / L) aqueous solution and tetrahydropyrrole (10 mmol) at once. The reaction mixture was stirred at room temperature for about 30 minutes. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be shown in 2o in the above reaction formula. Synthesis of methyl benzoate triazene 2p

[0061]

[0062] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), methyl 4-aminobenzoate (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2p in the above reaction formula.

[0063] Synthesis of 3-benzyltriazene 2q:

[0064]

[0065] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-benzylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2q in the above reaction formula.

[0066] Synthesis of 4-(4-methoxyphenoxy)triazene 2r:

[0067]

[0068] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 4-(4-methoxyphenoxy)aniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C. An aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2r in the above reaction formula.

[0069] Synthesis of 4-methyldiphenyl ether triazene 2s:

[0070]

[0071] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 4-amino-4'-methyl diphenyl ether (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C. An aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2s in the above reaction formula.

[0072] Synthesis of naphthalenetriazene 2t:

[0073]

[0074] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 2-naphthylamine (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2t in the above reaction formula.

[0075] Synthesis of N-methylquinoxalinone 1a:

[0076]

[0077] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) was added to ethyl glyoxylate (5.5 mmol). The reaction solvent was stirred and heated to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3-1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 The mixture was dried, filtered and evaporated. The desired target product was purified by column chromatography (petroleum ether / ethyl acetate) (15:1-3:1) gradient elution. Its structure was confirmed by NMR to be as shown in the above reaction formula 1a.

[0078] Synthesis of N-ethylquinoxalinone 1c:

[0079]

[0080] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of iodoethane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by nuclear magnetic resonance to be the product N-ethylquinoxalinone 1c shown in the above reaction formula.

[0081] Synthesis of N-propylquinoxalinone 1d:

[0082]

[0083] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Then, quinoxalinone (5 mmol) and DMF (15 mL) were added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of 1-iodopropane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product N-propylquinoxalinone 1d shown in the above reaction formula.

[0084] Synthesis of N-allylquinoxalinone 1e:

[0085]

[0086] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of acryloyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product shown in the above reaction formula, N-allylquinoxalinone 1e.

[0087] Synthesis of N-propargylquinoxalinone 1f:

[0088]

[0089] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. The reaction solvent was stirred and heated to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of 3-chloropropyne (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product N-propargylquinoxalinone 1f shown in the above reaction formula.

[0090] Synthesis of 1-(cyclopropylmethyl)quinoxalinone 1g:

[0091]

[0092] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. The reaction solvent was stirred and heated to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of (iodomethyl) cyclopropane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 The mixture was dried, filtered and evaporated. The desired target product was purified by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) and was confirmed by NMR to be 1 g of the product 1-(cyclopropylmethyl)quinoxalinone shown in the above reaction formula.

[0093] Synthesis of 1-(cyclohexylmethyl)quinoxalinone 1h:

[0094]

[0095] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of (iodomethyl) cyclohexane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 1-(cyclohexylmethyl)quinoxalinone 1h shown in the above reaction formula.

[0096] Synthesis of ethyl 2-(2-oxoquinoxaline-1(2-hydrogen)-yl)acetate 1i:

[0097]

[0098] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by ethyl chloroacetate (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 The mixture was dried, filtered and evaporated. The desired target product was obtained by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) and gradient elution purification. The product was confirmed by NMR to be ethyl 2-(2-oxoquinoxaline-1(2-hydrogen)-yl)acetate 1i as shown in the above reaction formula.

[0099] Synthesis of 1-(2-oxo-2-phenylethyl)quinoxaline-2(1H)-one 1j:

[0100]

[0101] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of phenacyl chloride (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 The mixture was dried, filtered and evaporated. The desired target product was purified by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) and was confirmed by NMR to be the product 1-(2-oxo-2-phenylethyl)quinoxaline-2(1H)-one 1j shown in the above reaction formula.

[0102] Synthesis of 6-bromo-1-methylquinoxalinone 1k:

[0103]

[0104] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of 4-bromobenzene-1,2-diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. Take the organic phase (ethyl acetate phase) and add anhydrous Na 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 6-bromo-1-methylquinoxalinone 1k shown in the above reaction formula.

[0105] Synthesis of 1,6,7-trimethylquinoxalinone 1l:

[0106]

[0107] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of 4,5-dimethylbenzene-1,2-diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 1,6,7-trimethylquinoxalinone 11 shown in the above reaction formula.

[0108] Synthesis of 6,7-dichloro-1-methylquinoxalinone 1m:

[0109]

[0110] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of 4,5-dichlorobenzene-1,2-diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 6,7-dichloro-1-methylquinoxalinone 1m shown in the above reaction formula.

[0111] Synthesis of 1,3-Bis-butylsulfonic Acid Imidazolium Ionic Liquid IL1

[0112]

[0113] The synthesis process of 1,3-bis-butylsulfonic acid imidazolate acidic ionic liquid. It is through the reaction of 1,4-butanesulfonic acid lactone (0.3 mol) and (0.6 mol) N-(trimethylsilyl) imidazole at 80°C for 24 hours, and then the resulting zwitterion is acidified with 18.4 mol / L concentrated sulfuric acid at 80°C for 72 hours. After the reaction is completed, all the mixtures obtained by the reaction are dissolved with 20 mL of distilled water, and repeatedly washed three times with ether (15 mL), and then dried under vacuum (100°C) for 2 hours to obtain the desired ionic liquid 1,3-bis-butylsulfonic acid imidazolate acidic ionic liquid, and confirmed by nuclear magnetic resonance and high-resolution mass spectrometry as the product shown in the above reaction formula.

[0114] Synthesis of 1-Ethyl-3-Butylsulfonic Acid Imidazolium Acidic Ionic Liquid IL2

[0115]

[0116] The synthesis process of 1-ethyl-3-butanesulfonic acid imidazolate acidic ionic liquid. It is prepared by reacting 1,4-butanesulfonic acid lactone (0.3 mol) with (0.3 mol) 1-ethyl imidazolate at 80°C for 24 hours, and then hydrochloric acidizing the obtained 1-ethyl-3-butanesulfonic acid imidazolate with 18.4 mol / L concentrated sulfuric acid at 80°C for 72 hours. After the reaction is completed, all the mixture obtained by the reaction is dissolved with 20 mL of distilled water-soluble mixture, and repeatedly washed three times with ether (15 mL), and then dried under vacuum (80°C) for 3 hours to obtain the desired ionic liquid 1-ethyl-3-butanesulfonic acid imidazolate acidic ionic liquid, and confirmed as the product shown in the above reaction formula by nuclear magnetic resonance and high-resolution mass spectrometry.

[0117] The invention has the beneficial effects of ion liquid-induced efficient CH-grouping reaction of quinoxalinone compounds and aryl triazene. Specifically, it relates to an electrochemical synthesis method of 3-arylquinoxalinone compounds, using aryl triazene as a stable arylation reagent and ionic liquid as a promoter and electrolyte for reaction. Under mild, metal-free and oxidant-free conditions, a variety of 3-arylquinoxalinone compounds and arylated quinoxaline compounds are generated in moderate to excellent yields. This scheme has the remarkable characteristics of simple operation, excellent functional group tolerance, high selectivity, strong product derivatization, and suitability for gram-level continuous flow chemical synthesis.

[0118] The invention uses an aromatic triazene with good stability, easy preparation and multiple reaction sites as an arylation reagent, uses an ionic liquid as an electrolyte and a promoter at room temperature, and uses DMSO as a solvent to realize a cross-coupling reaction between an aromatic triazene and a quinoxalinone under electrochemical conditions. The invention has the advantages that the reaction scale is easy to scale up, the operation is simple, the reaction conditions are mild, the substrate has a wide range of application, the scalability is strong, and the raw materials are simple and easy to obtain. BRIEF DESCRIPTION OF THE DRAWINGS

[0119] Figure 1 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 1.

[0120] Figure 2 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 2.

[0121] Figure 3 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 3.

[0122] Figure 4 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 4.

[0123] Figure 5 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 4.

[0124] Figure 6 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 6.

[0125] Figure 7 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 7.

[0126] Figure 8 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 8.

[0127] Fig. 9 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 9.

[0128] Fig.10 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 10.

[0129] Fig.11 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 11.

[0130] Fig.12 The following are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 12.

[0131] Fig.13 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 13.

[0132] Fig.14 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 14.

[0133] Fig.15 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 15.

[0134] Fig.16 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 16.

[0135] Fig.17 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 17.

[0136] Fig.18 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 18.

[0137] Fig.19 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 19.

[0138] Fig. 20 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 20.

[0139] Fig.21 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 21.

[0140] Fig. 22 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 22.

[0141] Fig.23 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 23.

[0142] Fig.24 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 24.

[0143] Fig.25 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 25.

[0144] Fig.26 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 26.

[0145] Fig. 27 These are the hydrogen and carbon nuclear magnetic resonance spectra of Example 27.

[0146] Fig.28 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 28.

[0147] Fig.29 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 29.

[0148] Fig.30 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 30.

[0149] Fig.31 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 31.

[0150] Fig.32 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 32.

[0151] Fig.33 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 33.

[0152] Fig.34 The nuclear magnetic resonance hydrogen spectrum and carbon spectrum of Example 34

[0153] Fig.35 These are the hydrogen and carbon nuclear magnetic resonance spectra of Example 35.

[0154] Fig.36 These are the hydrogen and carbon nuclear magnetic spectra of the nuclear magnetic resonance instrument of Example 36. DETAILED DESCRIPTION

[0155] The present invention is further described in detail in conjunction with the following specific examples, and the protection content of the present invention is not limited to the following examples. Without departing from the spirit and scope of the inventive concept, the changes and advantages that can be thought of by those skilled in the art are included in the present invention, and the attached claims are the scope of protection. The process, conditions, reagents, experimental methods, etc. for implementing the present invention, except for the contents specifically mentioned below, are all common knowledge and common common sense in the art, and the present invention has no special restrictions. The products of the embodiments include known compounds, and the data given in the following examples include specific operations and reaction conditions and products. The purity of the product is identified by nuclear magnetic resonance and high-resolution mass spectrometry.

[0156] Synthesis of p-methyltriazene 2a:

[0157]

[0158] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-methylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2a in the above reaction formula.

[0159] Synthesis of phenyltriazene 2b:

[0160]

[0161] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), aniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2b in the above reaction formula.

[0162] Synthesis of o-methyltriazene 2c:

[0163]

[0164] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), o-methylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2c in the above reaction formula.

[0165] Synthesis of m-methyltriazene 2d:

[0166]

[0167] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-methylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2d in the above reaction formula.

[0168] Synthesis of p-ethyltriazene 2e:

[0169]

[0170] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-ethylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be shown in 2e in the above reaction formula.

[0171] Synthesis of tert-butyltriazene 2f:

[0172]

[0173] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-tert-butylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2f in the above reaction formula.

[0174] Synthesis of 4-dodecyltriazene 2g:

[0175]

[0176] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 4-dodecylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2g in the above reaction formula.

[0177] Synthesis of p-methoxytriazene 2h:

[0178]

[0179] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-methoxyaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2h in the above reaction formula.

[0180] Synthesis of p-fluorotriazene 2i:

[0181]

[0182] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-Fluoroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be shown in 2i in the above reaction formula.

[0183] Synthesis of p-chlorotriazene 2j:

[0184]

[0185] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-chloroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2j in the above reaction formula.

[0186] Synthesis of p-bromotriazene 2k:

[0187]

[0188] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-bromoaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2k in the above reaction formula.

[0189] Synthesis of p-iodotriazene 2l:

[0190]

[0191] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-iodoaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 21 in the above reaction formula.

[0192] Synthesis of m-fluorotriazene 2m:

[0193]

[0194] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-fluoroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2m in the above reaction formula.

[0195] Synthesis of m-chlorotriazene 2n:

[0196]

[0197] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions[J]. J. Org. Chem., 2023, 88(15): 11056-11068.), m-chloroaniline (10 mmol) was added to a 100 mL round-bottom flask, and then concentrated hydrochloric acid (2 mL) with a molar concentration of 12 mol / L was slowly added to the above aniline at 0°C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was stirred in an ice bath for about 15 min, and then added to a 0-2°C solution containing 10 mL of potassium carbonate (1.2 mol / L) aqueous solution and tetrahydropyrrole (10 mmol) at once. The reaction mixture was stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance as shown in 2n in the above reaction formula.

[0198] Synthesis of bromotriazene 2o:

[0199]

[0200] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), m-bromoaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was stirred in an ice bath for about 15 minutes, and then added into a 0-2°C solution containing 10 mL of potassium carbonate (1.2 mol / L) aqueous solution and tetrahydropyrrole (10 mmol) at once. The reaction mixture was stirred at room temperature for about 30 minutes. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be shown in 2o in the above reaction formula. Synthesis of methyl benzoate triazene 2p

[0201]

[0202] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), methyl 4-aminobenzoate (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2p in the above reaction formula.

[0203] Synthesis of m-benzyltriazene 2q:

[0204]

[0205] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), p-benzylaniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2q in the above reaction formula.

[0206] Synthesis of 4-(4-methoxyphenoxy)triazene 2r:

[0207]

[0208] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 4-(4-methoxyphenoxy)aniline (10 mmol) was added to a 100 mL round-bottom flask, and then 12 mol / L concentrated hydrochloric acid (2 mL) was slowly added to the above aniline at 0 ° C. An aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2r in the above reaction formula.

[0209] Synthesis of 4-methyldiphenyl ether triazene 2s:

[0210]

[0211] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 4-amino-4'-methyl diphenyl ether (10 mmol) was added to a 100 mL round-bottom flask, and then concentrated hydrochloric acid (2 mL) with a molar concentration of 12 mol / L was slowly added to the above aniline at 0°C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added all at once to a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol). The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography, and its structure was confirmed by nuclear magnetic resonance to be as shown in 2s in the above reaction formula.

[0212] Synthesis of naphthalenetriazene 2t:

[0213]

[0214] According to previous literature reports (Gao J, Song Q, Zhang L, et al. Pd-Catalyzed C-7 Arylation of Indolines with Aryltriazenes under Mild Conditions [J]. J. Org. Chem., 2023, 88 (15): 11056-11068.), 2-naphthylamine (10 mmol) was added to a 100 mL round-bottom flask, and then concentrated hydrochloric acid (2 mL) with a molar concentration of 12 mol / L was slowly added to the above aniline at 0°C, and an aqueous solution (5 mL) of sodium nitrite (11 mmol) was prepared and added dropwise to the hydrochloric acid solution of aniline. The obtained diazonium salt solution was continued to be stirred in an ice bath for about 15 min, and then added into a 0-2°C solution containing 10 mL of an aqueous solution of potassium carbonate (1.2 mol / L) and tetrahydropyrrole (10 mmol) at once. The reaction mixture was continued to be stirred at room temperature for about 30 min. After the reaction was completed by monitoring by thin layer chromatography, the obtained product was recrystallized with ethanol or separated and purified by column chromatography. Its structure was confirmed by nuclear magnetic resonance to be as shown in 2t in the above reaction formula.

[0215] Synthesis of N-methylquinoxalinone 1a:

[0216]

[0217] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by nuclear magnetic resonance to be the product N-methylquinoxalinone 1a shown in the above reaction formula.

[0218] Synthesis of N-ethylquinoxalinone 1c:

[0219]

[0220] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of iodoethane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by nuclear magnetic resonance to be the product N-ethylquinoxalinone 1c shown in the above reaction formula.

[0221] Synthesis of N-propylquinoxalinone 1d:

[0222]

[0223] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Then, quinoxalinone (5 mmol) and DMF (15 mL) were added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of 1-iodopropane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product N-propylquinoxalinone 1d shown in the above reaction formula.

[0224] Synthesis of N-allylquinoxalinone 1e:

[0225]

[0226] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of acryloyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product shown in the above reaction formula, N-allylquinoxalinone 1e.

[0227] Synthesis of N-propargylquinoxalinone 1f:

[0228]

[0229] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. The reaction solvent was stirred and heated to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of 3-chloropropyne (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product N-propargylquinoxalinone 1f shown in the above reaction formula.

[0230] Synthesis of 1-(cyclopropylmethyl)quinoxalinone 1g:

[0231]

[0232] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. The reaction solvent was stirred and heated to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of (iodomethyl) cyclopropane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 The mixture was dried, filtered and evaporated. The desired target product was purified by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) and was confirmed by NMR to be 1 g of the product 1-(cyclopropylmethyl)quinoxalinone shown in the above reaction formula.

[0233]

[0234] Synthesis of 1-(cyclohexylmethyl)quinoxalinone 1h:

[0235] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of (iodomethyl) cyclohexane (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 1-(cyclohexylmethyl)quinoxalinone 1h shown in the above reaction formula.

[0236] Synthesis of ethyl 2-(2-oxoquinoxaline-1(2-hydrogen)-yl)acetate 1i:

[0237]

[0238] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by ethyl chloroacetate (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by nuclear magnetic resonance to be the product shown in the above reaction formula, ethyl 2-(2-oxoquinoxaline-1(2-hydrogen)-yl)acetate 1i.

[0239] Synthesis of 1-(2-oxo-2-phenylethyl)quinoxaline-2(1H)-one 1j:

[0240]

[0241] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of o-aryl diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by dropwise addition of phenacyl chloride (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 The mixture was dried, filtered and evaporated. The desired target product was purified by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) and was confirmed by NMR to be the product 1-(2-oxo-2-phenylethyl)quinoxaline-2(1H)-one 1j shown in the above reaction formula.

[0242] Synthesis of 6-bromo-1-methylquinoxalinone 1k:

[0243]

[0244] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of 4-bromobenzene-1,2-diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 6-bromo-1-methylquinoxalinone 1k shown in the above reaction formula.

[0245] Synthesis of 1,6,7-trimethylquinoxalinone 1l:

[0246]

[0247] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of 4,5-dimethylbenzene-1,2-diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 1,6,7-trimethylquinoxalinone 11 shown in the above reaction formula.

[0248] Synthesis of 6,7-dichloro-1-methylquinoxalinone 1m:

[0249]

[0250] According to previous literature reports (Wang, B.; Feng, Y, et al. Photo-Driven Direct C-HArylation of Quinoxalin-2(1H)-Ones with Aryltriazenes under Catalyst-Free and Ambient Conditions [J]. Eur. J. Org. Chem., 2023, 26, e202300044.), an ethanol suspension (20 mL) of 4,5-dichlorobenzene-1,2-diamine (5 mmol) and ethyl glyoxylate (5.5 mmol) were mixed. Stir the reaction and heat to reflux for 16 h. After the reaction was completed (TLC monitoring), the precipitate was filtered, washed with ethanol at -3 to 1 ° C, and finally dried to obtain quinoxalinone. Quinoxalinone (5 mmol) and DMF (15 mL) were then added to a 100 mL round-bottom flask with a stirring bar, followed by potassium carbonate (828 mg, 6 mmol), followed by methyl iodide (8 mmol). The reaction mixture was stirred at room temperature for 12 h, poured into 30 mL of water, extracted with 30 mL of ethyl acetate, and if no stratification occurred, 10 mL of saturated brine was added. 2 SO 4 Dry, filter, and evaporate. Purify by column chromatography (petroleum ether / ethyl acetate = 15:1-3:1, volume ratio, linear gradient elution) to obtain the desired target product, which was confirmed by NMR to be the product 6,7-dichloro-1-methylquinoxalinone 1m shown in the above reaction formula.

[0251] Synthesis of 1,3-Bis-butylsulfonic Acid Imidazolium Ionic Liquid IL1

[0252]

[0253] The synthesis process of 1,3-bis-butylsulfonic acid imidazolate acidic ionic liquid. It is through the reaction of 1,4-butanesulfonic acid lactone (0.3 mol) and (0.6 mol) N-(trimethylsilyl) imidazole at 80°C for 24 hours, and then the resulting zwitterion is acidified with 18.4 mol / L concentrated sulfuric acid at 80°C for 72 hours. After the reaction is completed, all the mixtures obtained by the reaction are dissolved with 20 mL of distilled water, and repeatedly washed three times with ether (15 mL), and then dried under vacuum (100°C) for 2 hours to obtain the desired ionic liquid 1,3-bis-butylsulfonic acid imidazolate acidic ionic liquid, and confirmed by nuclear magnetic resonance and high-resolution mass spectrometry as the product shown in the above reaction formula.

[0254] Synthesis of 1-Ethyl-3-Butylsulfonic Acid Imidazolium Acidic Ionic Liquid IL2

[0255]

[0256] The synthesis process of 1-ethyl-3-butanesulfonic acid imidazolate acidic ionic liquid. It is prepared by reacting 1,4-butanesulfonic acid lactone (0.3 mol) with (0.3 mol) 1-ethyl imidazolate at 80°C for 24 hours, and then hydrochloric acidizing the obtained 1-ethyl-3-butanesulfonic acid imidazolate with 18.4 mol / L concentrated sulfuric acid at 80°C for 72 hours. After the reaction is completed, all the mixture obtained by the reaction is dissolved with 20 mL of distilled water-soluble mixture, and repeatedly washed three times with ether (15 mL), and then dried under vacuum (80°C) for 3 hours to obtain the desired ionic liquid 1-ethyl-3-butanesulfonic acid imidazolate acidic ionic liquid, and confirmed as the product shown in the above reaction formula by nuclear magnetic resonance and high-resolution mass spectrometry.

[0257] Embodiment 1:

[0258]

[0259] In an 8 mL reaction tube, N-methylquinoxalinone 1a (32.04 mg, 0.2 mmol), p-methyltriazene 2a (94.63 mg, 0.5 mmol), ionic liquid IL1 (175.22 mg, 0.4 mmol) and DMSO (4 mL) were added in sequence to obtain a mixture. The mixture was reacted for 4 h in an IKA ElectraSyn 2.0pro electrochemical instrument (German IKA / ElectraSyn 2.0 electrochemical instrument, with a positive electrode of C and a negative electrode of Ni, and an electrolytic cell without a diaphragm for electrochemical reaction) at a current of 7 mA. After the reaction, the mixture was extracted with 8 mL of dichloromethane and 8 mL of water (8 mL of dichloromethane and 8 mL of water were added to the mixture), the organic phase was dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting mixture was purified by gradient elution of silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 20:1-5:1, v / v, linear gradient) to obtain a yellow solid 3aa (46.0 mg, yield 92%). The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 1-methyl-3-(p-tolyl)quinoxalin-2(1H)-one (3aa): Melting point: 159.7-161.1°C. 1 H NMR (600 MHz, CDCl 3 )δ8.2(d,J=8.3Hz,2H),7.92(dd,J=8.0,1.5Hz,1H),7.55–7.52(m,1H),7.36–7. 34(m,1H),7.31(d,J=8.4Hz,1H),7.28(d,J=7.9Hz,2H)3.75(s,3H),2.42(s,3H).13 C NMR (150 MHz, CDCl 3 )δ154.8,154.0,140.6,133.4,133.3,133.2,130.3,130.0,129.5,128.8,123.7,113.5,29.3,21.5.

[0260] Embodiment 2:

[0261] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2b (87.62 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ab (38.2 mg, yield 81%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 1-methyl-3-phenylquinoxalin-2(1H)-one(3ab): Melting point: 144.2-145.5℃. 1 H NMR (600 MHz, CDCl 3 )δ8.33–8.30(m,2H),7.95(dd,J=8.0,1.5Hz,1H),7.59–7.56(m,1H),7.49 –7.48(m,3H),7.39–7.36(m,1H),7.34(dd,J=8.3,1.3Hz,1H),3.78(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.9,154.3,136.2,133.5,133.3,130.6,130.5,129.7,128.2,123.9,113.7,29.4.

[0262] Embodiment 3:

[0263] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2c (94.63 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ac (31.0 mg, yield 62%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 1-methyl-3-(o-tolyl)quinoxalin-2(1H)-one (3ac): Yellow solid. Melting point: 89.1-90.1°C. 1 H NMR (600 MHz, CDCl 3)δ7.93(dd,J=7.7,0.96Hz,1H),7.63–7.60(m,1H),7.46(d,J=7.5Hz,1H),7.40–7.34(m,3H),7.30(d,J=7.0Hz,2H),,3.78(s,3H),2.35(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ158.6,154.7,137.0,136.3,133.7,133.0,130.7,130.7,130.6,129.5,129.3,125.8,123.9,113.8,29.5,20.1

[0264] Embodiment 4:

[0265] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2d (94.63 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ad (44.0 mg, yield 88%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 1-methyl-3-(m-tolyl)quinoxalin-2(1H)-one (3ad): Melting point: 108.6-109.2℃. 1 H NMR (600 MHz, CDCl 3 )δ8.10–8.09(m,2H),7.95(dd,J=8.0,1.5Hz,1H),7.58–7.55(m,1H),7.39–7.36(m ,2H),7.34(dd,J=8.4,1.2Hz,1H),7.30(d,J=7.5Hz,1H),3.78(s,3H),2.45(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.9,154.6,137.8,136.2,133.5,133.3,131.3,130.6,130.4,130.1,128.1,126.9,123.8,113.7,29.4,21.7.

[0266] Embodiment 5:

[0267] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2e (101.65 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ae (43.3 mg, yield 82%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(4-ethylphenyl)-1-methylquinoxalin-2(1H)-one (3ae): Melting point: 125.4-126.2℃. 1 H NMR (600 MHz, CDCl 3 )δ8.25(d,J=8.3Hz,2H),7.94(dd,J=8.0,1.5Hz,1H),7.57–7.54(m,1H),7.36(td,J=7.8,1. 3Hz,1H),7.32(t,J=8.2,Hz,3H),3.77(s,3H),2.72(q,J=7.6Hz,2H),1.28(t,J=7.6Hz,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.9,154.3,147.0,133.7,133.4,133.3,130.5,130.2,129.7,127.8,123.8,113.7,29.4,29.0,15.6.

[0268] Embodiment 6:

[0269] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2f (115.59 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3af (52 mg, yield 89%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(4-(tert-butyl)phenyl)-1-methylquinoxalin-2(1H)-one (3af): Melting point: 90.8-92.2℃. 1 H NMR (600 MHz, CDCl 3 )δ8.25(d,J=8.5Hz,2H),7.93(dd,J=8.0,1.5Hz,1H),7.56–7.53(m,1H),7.51(d,J=8 .5Hz,2H)7.35(td,J=7.6,1.1Hz,1H),7.32(d,J=8.3Hz,1H)3.76(s,3H),1.37(s,9H). 13 CNMR (150MHz, CDCl3 )δ154.9,154.3,153.7,133.5,133.4,133.3,130.5,130.1,129.4,125.2,123.7,113.6,35.0,31.3,29.4.

[0270] Embodiment 7:

[0271] The reaction steps and operating conditions were the same as those in Example 1, except that 2 g (171.65 mg, 0.5 mmol) of raw material was added to the reaction system instead of the reaction substrate (2a), and the yellow solid new compound 3ag (50.7 mg, yield 65%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product were 1-methyl-3-(4-undecylphenyl)quinoxalin-2(1H)-one (3ag): Melting point: 60.4-61.7°C. 1 HNMR (600MHz, CDCl 3 )δ8.25(d,J=8.2Hz,2H),7.93(dd,J=7.9,1.5Hz,1H),7.56–7.53(m,1H)7.37–7.34(m,1H),7.32(dd,J=8.4,1.2Hz,1H ),7.29(d,J=8.2Hz,2H),3.76(s,3H),2.67(t,J=7.7Hz,2H),1.68–1.63(m,2H),1.27(s,18H),0.89(t,J=6.8Hz,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.9,154.2,145.8,133.6,133.4,133.3,130.4,130.1,129.6,128.3,123.7,113 .6,36.1,32.1,31.4,29.8,29.8,29.7,29.7,29.5,29.4,29.4,22.8,14.3.HRMS(ESI + ):m / z calcd.forC 27 H 36 ON 2 [M+Na] + :427.2720,Found:427.2714.

[0272] Embodiment 8:

[0273] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is 2h (102.56 mg, 0.5 mmol) instead of the reaction substrate (2a), and the yellow solid 3ah (44.2 mg, yield 85%) is obtained by purification. The target product is confirmed by nuclear magnetic resonance detection. The product parameters are 3-(4-methoxyphenyl)-1-methylquinoxalin-2(1H)-one (3ah): Eluent: petroleum ether / EtOAc = 15:1 to 3:1 (v / v). 44.2 mg, 85% yield. Yellow solid. Melting point: 125.3-126.9°C. 1 H NMR (600 MHz, CDCl 3 )δ8.40(d,J=8.9Hz,2H),7.92(dd,J=8.0,1.5Hz,1H),7.55–7.52(m,1H),7.37–7.34 (m,1H),7.32(dd,J=8.4,1.3Hz,1H),7.0(d,J=8.9Hz,2H)3.88(s,3H),3.77(s,3H). 13 CNMR (150MHz, CDCl 3 )δ161.5,154.9,153.2,133.2,131.4,130.1,129.8,128.8,123.7,113.5,55.4,29.3

[0274] Embodiment 9:

[0275] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2i (96.55 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ai (39.1 mg, yield 77%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(4-fluorophenyl)-1-methylquinoxalin-2(1H)-one (3ai): Yellow solid. Melting point: 151.6-152.2℃. 1 HNMR (600MHz, CDCl 3)δ8.41–8.38(m,2H),7.92(dd,J=8.0,1.4Hz,1H),7.58–7.55(m,1H),7.38 –7.36(m,1H),7.33(dd,J=8.5,1.2Hz,1H),7.17–7.13(m,2H),3.76(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ165.4(d,J C-F =249.0Hz),154.8,152.8,133.4,133.1,132.3(d,J C-F =3.0Hz),131.9(d,J C-F =7.5Hz),130.5,(d,J C-F =4.5Hz),123.9,115.2,115.1 113.7,29.4.

[0276] Embodiment 10:

[0277] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2j (104.84 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3aj (35.1 mg, yield 65%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(4-chlorophenyl)-1-methylquinoxalin-2(1H)-one (3aj): Melting point: 177.6-179.2℃. 1 H NMR (600 MHz, CDCl 3 )δ8.34(d,J=8.6Hz,2H),7.93(dd,J=8.0,1.4Hz,1H),7.59–7.56(m,1H),7.44(d ,J=8.6Hz,2H),7.38(td,J=7.4,1.2Hz,1H),7.33(d,J=8.3Hz,1H),3.76(s,3H). 13 C NMR (150MHz, δ154.7,152.8,136.7,134.6,133.5,133.1,131.1,130.7,130.6,128.4,124.0,113.8,29.5.

[0278] Embodiment 11:

[0279] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2k (127.07.07 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ak (47.1 mg, yield 75%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(4-bromophenyl)-1-methylquinoxalin-2(1H)-one (3ak): Melting point: 169.2-170.6°C. 1 H NMR (600 MHz, CDCl 3 )δ8.27(d,J=8.6Hz,2H),7.93(dd,J=8.0,1.5Hz,1H),7.60(d,J=8.6Hz,2H),7 .59–7.57(m,1H),7.39–7.37(m,1H)7.34(dd,J=8.4,1.1Hz,1H),3.77(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.7,152.9,135.0,133.5,133.1,131.4,131.3,130.7,130.7,125.2,124.0,113.8,29.5.

[0280] Embodiment 12:

[0281] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2l (150.57 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3al (29.0 mg, yield 40%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(4-iodophenyl)-1-methylquinoxalin-2(1H)-one (3al): Melting point: 153.9-154.1°C. 1 H NMR (600 MHz, CDCl 3 )δ8.12(d,J=8.6Hz,2H),7.93(dd,J=8.0,1.5Hz,1H),7.82(d,J=8.6Hz,2H),7 .60–7.57(m,1H),7.39–7.37(m,1H),7.34(dd,J=8.5,1.2Hz,1H).3.77(s,3H). 13 C NMR (150 MHz, CDCl 3)δ154.7,153.0,137.4,135.6,133.5,133.2,131.4,130.8,130.7,129.7,128.2,124.0,113.8,97.6,29.5.

[0282] Embodiment 13:

[0283] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2m (96.55 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3am (36.6 mg, yield 72%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(3-Fluorophenyl)-1-methylquinoxalin-2(1H)-one (3am): Melting point: 172.2-173.3°C. 1 H NMR (600 MHz, CDCl 3 )δ8.18(d,J=7.9,1H),8.11(dt,J=2.2,10.3Hz,1H),7.93(dd,J=1.4,8.5Hz,1H),7.59–7.56(m,1H) ,7.45–7.42(m,2H),7.38(t,J=8.2),7.33(d,J=8.3,1H),8.11(td,J=2.7,8.3Hz,1H),3.76(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ162.6(d,J C-F =244.5Hz),154.6,152.5,138.2(d,J C-F =7.5Hz),133.5,133.0,130.9,130.7,129.6(d,J C-F =9Hz),125.4(d,J C-F =3Hz),124.0,117.3(d,J C-F =21Hz),116.65,(d,J C-F =24Hz),11.74,29.4.

[0284] Embodiment 14:

[0285] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2n (104.84 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3an (35.2 mg, yield 65%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(3-Chlorophenyl)-1-methylquinoxalin-2(1H)-one (3an): Melting point: 180.6-182.2℃. 1 H NMR (600 MHz, CDCl 3 )δ8.36(t,J=1.91H),8.27(dd,J=7.7,1.4Hz,1H),7.92(dd,J=8.0,1.5,1H),7.58–7.55(m,1H),7. 45–7.43(m,1H),7.40(d,J=7.8Hz,1H),7.38–7.35(m,1H),7.31(dd,J=8.5,1.2,1H),3.74(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.6,152.4,137.8,134.2,133.5,133.0,130.9,130.7,130.4,129.6,129.4,127.9,124.0,113.7,29.4

[0286] Embodiment 15:

[0287] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2o (127.07.07 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ao (32.8 mg, yield 52%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(3-Bromophenyl)-1-methylquinoxalin-2(1H)-one (3ao): Melting point: 185.6-186.2°C. 1 H NMR (600 MHz, CDCl 3 )δ8.51(t,J=1.91H),8.33(d,J=7.8Hz,1H),7.94(dd,J=8.0,1.5Hz,1H),7.61–7. 60(m,1H),7.60–7.58(m,1H),7.40–7.37(m,1H),7.36–7.33(m,2H),3.77(s,3H). 13C NMR (150 MHz, CDCl 3 )δ154.6,152.4,138.0,133.5,133.3,133.0,132.5,131.0,130.8,129.7,128.4,124.1 122.4,113.8,29.5.

[0288] Embodiment 16:

[0289] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2p (132.58 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ap (51.2 mg, yield 87%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(3-Bromophenyl)-1-methylquinoxalin-2(1H)-one (3ap): Melting point: 176.6-178.6°C. 1 H NMR (600 MHz, CDCl 3 )δ8.38(d,J=8.5Hz,2H),8.06(d,J=8.5Hz,=2H),7.91(dd,J=7.9,1.4Hz,1H),7.70 –7.67(m,1H),7.61(d,J=8.4Hz,=1H)7.44–7.41(m,1H),3.90(s,3H),3.70(s,3H). 13 CNMR (150MHz, CDCl 3 )δ154.6,152.4,138.0,133.5,133.3,133.0,132.5,131.0,130.8,129.7,128.4,124.1 122.4,113.8,29.5

[0290] Embodiment 17:

[0291] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2q (140.53 mg, 0.5 mmol) instead of the reaction substrate (2a), and the yellow solid new compound 3aq (44.4 mg, yield 68%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product were 3-(4-benzylphenyl)-1-methylquinoxalin-2(1H)-one (3aq): Melting point: 104.4-105.8°C 1 HNMR (600MHz, CDCl 3)δ8.25(d,J=8.2Hz,2H),7.93(dd,J=8.0,1.5Hz,1H),7.57–7.54(m,1H),7.38–7.35(m,1H)7 .32(t,J=8.6Hz,3H),7.29(d,J=7.0Hz,2H),7.22(d,J=6.0Hz,3H),4.06(s,2H),3.77(s,3H). 13 CNMR (150MHz, CDCl 3 )δ154.9,154.2,143.7,140.9,134.2,133.5,133.3,130.5,130.3,129.9,129.1 128.9,128.6,126.3,123.8,113.7,42.0,29.4.HRMS(ESI + ):m / z calcd.for C 22 H 18 N 2 ONa[M+Na] + :349.1311,Found:349.1304

[0292] Embodiment 18:

[0293] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2r (148.68 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow solid 3ar (50.1 mg, yield 70%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product were 3-(4-(4-methoxyphenoxy)phenyl)-1-methylquinoxalin-2(1H)-one (3ar): Melting point: 140.3-141.5°C. 1 H NMR (600 MHz, CDCl 3 )δ8.35(d,J=8.9Hz,2H),7.92(dd,J=8.0,1.5Hz,1H),7.57–7.54(m,1H),7.38–7.35(m,1H),7. 33(dd,J=8.4,1.2Hz,1H),7.05–7.01(m,4H),6.91(d,J=9.1Hz,2H),3.82(s,3H),3.77(s,3H). 13 CNMR (150MHz, CDCl 3)δ160.7,154.9,153.4,149.6,133.4,133.3,131.5,130.4,130.1,123.9,116.9,115.0,113.7,55.8,29.4.HRMS(ESI + ):m / z calcd.for C 22 H 18 N 2 O 3 Na[M+Na] + :381.1210,Found:381.1201

[0294] Embodiment 19:

[0295] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2s (140.68 mg, 0.5 mmol) instead of the reaction substrate (2a), and yellow oily liquid 3as (49.3 mg, yield 72%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product were 1-methyl-3-(4-(p-tolyloxy)phenyl)quinoxalin-2(1H)-one (3as) 1 H NMR (600 MHz, CDCl 3 )δ8.36(d,J=8.8Hz,2H),7.92(dd,J=8.0,1.5Hz,1H),7.57–7.54(m,1H),7.38–7.35(m,1H),7.33(dd,J=8.5 ,1.3Hz,1H),7.17(d,J=8.3Hz,2H),7.06(d,J=8.8Hz,2H),6.99(d,J=8.4Hz,2H),3.77(s,3H),2.36(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ160.1,154.9,154.1,153.4,133.6,133.4,133.3,131.6,130.7,130.5,130.4,130.2,123.9,119.8,117.5,113.7,29.4,20.9.HRMS(ESI + ):m / z calcd.for C 22 H 18 N 2 O 2 Na[M+Na] + :365.1261,Found:365.1255.

[0296] Embodiment 20:

[0297] The reaction steps and operating conditions were the same as those in Example 1. The difference from Example 1 was that the raw material added to the reaction system was 2t (112.68 mg, 0.5 mmol) instead of the reaction substrate (2a). Red solid 3at (38.9 mg, yield 68%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance. The parameters of the obtained product were 1-methyl-3-(naphthalen-2-yl)quinoxalin-2(1H)-one (3at). 4 :Melting point:155.3-156.9℃. 1 H NMR (600 MHz, CDCl 3 )δ8.00–7.96(m,2H),7.92–7.90(m,2H),7.77(dd,J=7.1,1.2Hz,1H),7.66–7.63(m, 1H),7.59(dd,J=8.2,7.1Hz,1H),7.51–7.45(m,2H),7.43–7.40(m,2H),3.82(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ157.5,155.1,134.0,133.9,133.8,133.1,131.6,130.9,130.7,130.2,128.6,127.8,126.6,126.0,125.4,125.1,124.0,113.9,29.6.

[0298] Embodiment 21:

[0299] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is quinoxalinone 1b (29.23 mg, 0.2 mmol) instead of the reaction substrate (1a), 3ba (33.1 mg, yield 70%). The target product was confirmed by nuclear magnetic resonance, and the obtained product parameters are 3-(p-tolyl)quinoxalin-2(1H)-one(3ba):. Yellow solid. Melting point: 241.6-243.2℃. 1 H NMR (600 MHz, DMSO-d 6 )δ12.53(s,1H),8.26(d,J=8.2Hz,2H),7.82(dd,J=8.0,1.4Hz,1H),7.54–7.51(m,1H)7.34–7.29(m,4H),2.38(s,3H). 13C NMR (150 MHz, DMSO-d 6 )δ154.6,153.8,140.1,132.9,132.0,131.9,130.1,129.2,128.6,128.5,123.4,115.0,21.1.

[0300] Embodiment 22:

[0301] The reaction steps and operating conditions were the same as those in Example 1. The difference from Example 1 was that the raw material added to the reaction system was 1c (34.82 mg, 0.2 mmol) instead of the reaction substrate (1a). Purification gave a yellow solid 3ca (42.8 mg, yield 81%). The target product was confirmed by nuclear magnetic resonance. The parameters of the obtained product were 1-ethyl-3-(p-tolyl)quinoxalin-2(1H)-one (3ca). 6 :Melting point:125.6-126.2℃., 1 H NMR (600 MHz, CDCl 3 )δ8.26(d,J=8.0Hz,2H),7.95(dd,J=8.2,1.6Hz,1H),7.56–7.53(m,1H),7.36–7.34(m ,2H),7.29(d,J=7.9Hz,2H),4.39(q,J=7.2Hz,2H),2.42(s,3H),1.42(t,J=7.1Hz,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.4,154.1,140.7,133.6,133.4,132.4,130.7,130.1,129.7,128.9,123.6,113.5,37.7,21.6,12.5

[0302] Embodiment 23:

[0303] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 1d (37.62 mg, 0.2 mmol) instead of the reaction substrate (1a), and the white solid 3da (41.7 mg, yield 75%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product were 1-propyl-3-(p-tolyl)quinoxalin-2(1H)-one (3da):. Melting point: 69.8-71.1°C. 1 H NMR (600 MHz, CDCl 3)δ8.26(d,J=8.3,2H),7.94(dd,J=8.0,1.4Hz,1H),7.55–7.52(m,1H),7.36–7.34(m,1H),7.32(d,J=8.2Hz,1H ),7.29(d,J=8.0Hz,2H),4.29–4.27(m,2H),2.42(s,3H),1.85(td,J=15.1,7.4Hz,2H),1.09(t,J=7.4Hz,3H). 13 CNMR (150MHz, CDCl 3 )δ154.6,154.1,140.7,133.6,133.5,132.6,130.7,130.1,129.7,128.9,123.6,113.7,44.2,21.6,20.8,11.6.HRMS(ESI + ):m / z calcd.forC 18 H 18 N 2 ONa[M+Na] + :301.1311,Found:301.1311.

[0304] Embodiment 24:

[0305] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 1e (37.22 mg, 0.2 mmol) instead of the reaction substrate (1a), and yellow solid 3ea (50.8 mg, yield 92%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 1-allyl-3-(p-tolyl)quinoxalin-2(1H)-one (3ea): Melting point: 98.6-99.5°C. 1 H NMR (600 MHz, CDCl 3 )8.27(d,J=8.2Hz,2H),7.94(dd,J=8.0,1.6Hz,1H),7.53–7.50(m,1H),7.36–7.34(m,1H),7.30(t,J=8.3Hz,3H) ,6.02–5.96(m,1H),5.29(dd,J=10.3,1.1Hz,1H),5.22(dd,J=17.3,1.3Hz,1H),4.98–4.97(m,1H),2.42(s,3H). 13 C NMR (150 MHz, CDCl 3)δ154.5,154.1,140.8,133.5,133.4,132.7,130.9,130.6,130.1,129.7,128.9,123.8,118.2,114.2,44.8,21.7

[0306] Embodiment 25:

[0307] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is 1f (36.81 mg, 0.2 mmol) instead of the reaction substrate (1a), and the yellow solid 3fa (45.0 mg, yield 82%) is purified. The target product is confirmed by nuclear magnetic resonance detection, and the obtained product parameters are 1-(prop-2-yn-1-yl)-3-(p-tolyl)quinoxalin-2(1H)-one (3fa): Melting point: 172.6-173.2℃. 1 H NMR (600 MHz, CDCl 3 )δ8.26(d,J=8.2Hz,2H),7.95(dd,J=8.0,1.5Hz,1H),7.60–7.57(m,1H),7.47(d,J=8.3Hz,1H),δ7 .40–7.38(m,1H),7.29(d,J=8.0Hz,2H),5.12(d,J=2.5Hz,2H),2.43(s,3H),2.30(t,J=2.5Hz,1H). 13 C NMR (150 MHz, CDCl 3 )δ154.0,153.9,141.0,133.5,133.2,131.9,130.6,130.3,129.7,129.0,124.2,114.1,73.2,31.8,21.7

[0308] Embodiment 26:

[0309] The reaction steps and operating conditions are the same as those in Example 1. The difference from Example 1 is that 1 g (40.02 mg, 0.2 mmol) of raw material is added to the reaction system instead of the reaction substrate (1a). Purification yields yellow solid 3ga (37.7 mg, yield 65%). The target product is confirmed by nuclear magnetic resonance detection. The obtained product parameters are 1-(cyclopropylmethyl)-3-(p-tolyl)quinoxalin-2(1H)-one(3ga):.Melting point:96.6-99.1℃. 1 H NMR (600 MHz, CDCl 3)δ8.24(d,J=8.2Hz,2H),7.95(dd,J=8.0,1.6Hz,1H),7.56–7.53(m,1H),7.44(dd,J=8.5,1.2Hz,1H),7.36– 7.33(m,1H)7.29(d,J=8.0Hz,2H),4.27(d,J=7.0Hz,2H),2.42(s,3H),1.36–1.29(m,1H),0.62–0.55(m,4H). 13 C NMR (150 MHz, CDCl 3 )δ154.9,154.4,140.7,133.6,133.5,132.8,130.7,130.0,129.7,128.9,123.6,113.9,46.4,21.6,9.8,4.3

[0310] Embodiment 27:

[0311] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is 1h (48.43 mg, 0.2 mmol) instead of the reaction substrate (1a), and the yellow solid new compound 3ha (42.9 mg, yield 62%) is purified. The target product is confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product are 1-(2-cyclohexylethyl)-3-(p-tolyl)quinoxalin-2(1H)-one (3ha): Melting point: 100.6-101.8℃. 1 H NMR (600 MHz, CDCl 3 )δ8.25(d,J=8.2Hz,2H)7.93(dd,J=7.9,1.5Hz,1H),7.54–7.51(m,1H),7.35–7.32(m,2H),7.29(d,J=7 .9Hz,2H),4.21(d,J=7.3Hz,2H),2.42(s,3H),1.98–1.94(m,1H),1.75–1.65(m,6H),1.21–1.19(m,4H). 13 C NMR (150 MHz, CDCl 3 )δ155.0,154.1,140.7,133.5,133.5,133.1,130.7,129.9,129.7,128.9,123.5,114.1,48.3,36.7,31.1,26.3,26.0,21.6.HRMS(ESI + ):m / z calcd.for C 22H 24 N 2 O[M+H] + :333.1961,Found:333.1956.

[0312] Embodiment 28:

[0313] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 1i (46.42 mg, 0.2 mmol) instead of the reaction substrate (1a), and yellow solid 3ia (47.7 mg, yield 74%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were ethyl 2-(2-oxo-3-(p-tolyl)quinoxalin-1(2H)-yl)acetate (3ia): Melting point: 159.8-161.1℃. 1 H NMR (600 MHz, CDCl 3 )δ8.27(d,J=8.3Hz,2H),7.95(dd,J=8.0,1.5Hz,1H),7.53–7.50(m,1H),7.38–7.35(m,1H),7.29(d,J=7 .9Hz,2H),7.09(d,J=7.2Hz,1H),5.08(s,2H),4.26(q,J=7.1Hz,2H),2.42(s,3H),1.28(t,J=7.1Hz,3H). 13 C NMR (150 MHz, CDCl 3 )δ167.4,154.5,153.8,140.9,133.3,133.1,132.5,130.8,130.3,129.7,128.9,128.1,124.1,113.1,62.2,43.9,21.6,14.2.

[0314] Embodiment 29:

[0315] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 1j (52.82 mg, 0.2 mmol) instead of the reaction substrate (1a), and yellow solid 3ja (36.8 mg, yield 52%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 1-(2-oxo-2-phenylethyl)-3-(p-tolyl)quinoxalin-2(1H)-one (3ja): Melting point: 185.8-186.1℃. 1 H NMR (600 MHz, CDCl3 )δ8.27(d,J=8.3Hz,2H),8.10(dd,J=8.2,1.2Hz,2H),7.97(dd,J=8.0,1.5Hz,1H),7.70–7.67(m,1H),7.57–7.55(m,2H ),7.46–7.43(m,1H),7.36–7.34(m,1H),7.29(d,J=7.7Hz,2H),6.98(dd,J=8.5,1.2Hz,1H),5.80(s,2H),2.42(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ191.4,154.6,153.8,140.9,134.8,134.4,133.5,133.3,132.9,130.8,130.2,129.7,129.2,129.0,128.3,123.6,113.5,48.8,21.7.

[0316] Embodiment 30:

[0317] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 1k (47.59 mg, 0.2 mmol) instead of the reaction substrate (1a), and yellow solid 3ka (34.1 mg, yield 52%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 6-bromo-1-methyl-3-(p-tolyl)quinoxalin-2(1H)-one (3ka): Melting point: 155.8-157.1℃. 1 H NMR (600 MHz, CDCl 3 )δ8.23(d,J=8.2Hz,2H),7.76(d,J=8.4Hz,1H),7.46–7.44(m,2H),7.28(d,J=8.0Hz,2H),3.71(s,3H),2.42(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.5,154.2,141.1,134.4,133.1,132.1,131.6,129.7,129.0,127.1,116.7,29.5,21.7.

[0318] Embodiment 31:

[0319] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material 11 (37.62 mg, 0.2 mmol) was added to the reaction system to replace the reaction substrate (1a) and purified to obtain a yellow solid 31a (44.1 mg, yield 72%). The target product was confirmed by nuclear magnetic resonance detection. The parameters of the obtained product were 1,6,7-trimethyl-3-(p-tolyl)quinoxalin-2(1H)-one (31a): Melting point: 195.8-196.7℃. 1 H NMR (600 MHz, CDCl 3 )δ8.22(d,J=8.2Hz,2H),7.68(s,1H),7.27(d,J=7.9Hz,2H),7.08(s,1H),3.73(s,3H),2.42(d,J=8.0Hz,6H),2.36(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ155.0,153.0,140.3,140.1,133.8,132.7,131.7,131.5,130.5,129.5,128.9,114.2,29.3,21.6,20.8,19.3.

[0320] Embodiment 32:

[0321] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is 1m (45.60 mg, 0.2 mmol) instead of the reaction substrate (1a), and the yellow solid 3ma (47.1 mg, yield 68%) is purified. The target product is confirmed by nuclear magnetic resonance detection, and the obtained product parameters are 6,7-dichloro-1-methyl-3-(p-tolyl)quinoxalin-2(1H)-one (3ma): Melting point: 183.8-185.1℃. 1 H NMR (600 MHz, CDCl 3 )δ8.23(d,J=8.3Hz,2H),7.97(s,1H),7.37(s,1H),7.27(d,J=8.5Hz,2H),3.68(s,3H),2.42(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ154.9,154.3,141.5,134.0,132.7,132.7,132.3,131.0,129.8,129.0,127.5,115.1,29.6,21.7

[0322] Embodiment 33:

[0323] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is 2-methylquinoxaline 1n (28.81 mg, 0.2 mmol) instead of the reaction substrate (1a), and red oily liquid 3na (15.7 mg, yield 30%) is obtained by purification. The target product is confirmed by nuclear magnetic resonance detection, and the obtained product parameters are 2-methyl-3-(p-tolyl)quinoxaline (3na): 1 H NMR (600 MHz, CDCl 3 )δ8.10(dd,J=7.8,1.9Hz,1H),8.05(dd,J=7.9,1.9Hz,1H),7.76–7.67(m,2 H),7.56(d,J=7.8Hz,2H),7.33(d,J=7.8Hz,2H),2.79(s,3H),2.45(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ155.1,152.8,141.3,140.8,138.3,136.3,129.7,129.4,129.4,129.3,129.0,128.4,24.6,21.5.

[0324] Embodiment 34:

[0325] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2-aminoquinoxaline 1o (29.01 mg, 0.2 mmol) instead of the reaction substrate (1a), and red solid 3oa (32.6 mg, yield 62%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(p-tolyl)quinoxalin-2-amine (3oa): Melting point: 173.8-175.1°C. 1 H NMR (600 MHz, CDCl 3 )δ7.95(dd,J=8.2,1.5Hz,1H),7.68–7.66(m,3H),7.59–7.57(m,1H),7.45–7.42(m,1H),7.34(d,J=7.8Hz,2H),5.23(s,2H),2.43(s,3H). 13 C NMR (150 MHz, CDCl 3)δ150.8,146.1,141.2,140.0,138.3,134.2,130.0,130.0,129.1,128.4,125.7,125.3,21.5.

[0326] Embodiment 35:

[0327] The reaction steps and operating conditions were the same as those in Example 1, except that the raw material added to the reaction system was 2-mercaptoquinoxaline 1p (32.41 mg, 0.2 mmol) instead of the reaction substrate (1a), and yellow oily liquid 3pa (26.9 mg, yield 48%) was obtained by purification. The target product was confirmed by nuclear magnetic resonance detection, and the obtained product parameters were 3-(p-tolyl)quinoxaline-2-thiol (3pa): 1 H NMR (600 MHz, CDCl 3 )δ8.40(s,1H),7.98(dd,J=8.3,1.5Hz,1H),7.90(dd,J=8.4,1.5Hz,1H),7.70–7.67( m,1H),7.64–7.61(m,2H),7.56(d,J=8.1Hz,2H),7.28(d,J=8.0Hz,2H),2.42(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ157.9,143.4,142.3,140.2,140.0,135.3,130.8,130.6,129.3,128.8,128.4,125.3,21.5

[0328] Embodiment 36:

[0329] The reaction steps and operating conditions are the same as those in Example 1, except that the raw material added to the reaction system is 2-methyldibenzoquinoxaline 1q (48.82 mg, 0.2 mmol) instead of the reaction substrate (1a), and the yellow solid new compound 3qa (30.4 mg, yield 52%) is purified. The target product is confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. The parameters of the obtained product are 2-methyl-3-(p-tolyl)dibenzo[f,h]quinoxaline (3qa): Melting point: 128.8-130.1℃. 1 H NMR (600 MHz, CDCl 3)δ9.27–9.26(m,2H),8.63–8.60(m,2H),7.77–7.34(m,5H),7.73–7.70(m,1H),7.38(d,J=7.4Hz,2H),2.92(s,3H),2.49(s,3H). 13 C NMR (150 MHz, CDCl 3 )δ152.7,150.8,138.9,138.8,138.6,136.7,131.4,131.2,130.3,130.0,129.6,12 9.2,129.1,129.0,127.6,127.6,125.5,125.4,122.9,122.8,24.3,21.5.HRMS(ESI + ):m / z calcd.for C 24 H 18 N 2 [M+H] + :335.1543,Found:335.1537

[0330] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An electrochemical synthesis method of 3-arylquinoxalinone compounds, characterized in that: Using quinoxalinone compound 1 and aryl triazene 2 as reaction substrates, and ionic liquid as electrolyte and promoter, the product 3 of arylation of quinoxalinone compound 3 is obtained under electrochemical reaction conditions; the synthesis route is shown in the following reaction formula: In the reaction formula, R1 is one or more of H, methyl, chlorine or bromine, and the number is 1-3; R2 is one or more of H, methyl, ethyl, methoxy, C2-C12 alkyl, tert-butyl, halogen, C2-C6 ester, benzyl, 4-methyldiphenyl ether and 4-methoxydiphenyl ether substituent, and a naphthalene ring formed by the benzene ring to which R2 is connected, and the number is 1-5, and the halogen is one or more of fluorine, chlorine, bromine and iodine; R3 is one or more of methyl, H, ethyl, propyl, allyl, propargyl, cyclopropyl, cyclopropylmethylene, benzyl, cyclohexylmethylene, benzoylmethyl, cyclohexyl, C2-C6 ester and benzoyl; "O / R4" represents one or more of "O or R4", and R4 is one or more of methyl, amino and thiol.

2. The synthesis method according to claim 1, characterized in that: The reaction is carried out in a solvent, and the solvent is one or more of methanol, ethanol, acetonitrile, N,N-dimethylformamide, trifluoroethanol, dimethyl sulfoxide, dimethyl sulfoxide and acetonitrile (volume ratio is 1:0.5-2). The best effect is achieved when the reaction solvent is dimethyl sulfoxide. The amount of the solvent is 3-10 mL, preferably 3-5 mL, of the solvent per 0.2 mmol of the quinoxaline compound.

3. The synthesis method according to claim 1, characterized in that: The ionic liquid is 1,3-bis(butylsulfonic acid imidazole) acidic ionic liquid 1-Ethyl-3-butanesulfonic acid imidazolium acidic ionic liquid Any one or two of the above substances are used as electrolytes and promoters for the reaction, and the amount of the substance used is 0.2-0.8 mmol, preferably 0.3-0.4 mmol, of ionic liquid per 0.2 mmol of quinoxalinone compound 1.

4. The synthesis method according to claim 1, characterized in that: The electrochemical reaction conditions are as follows: the reaction current is 4-7 mA, and the best effect is achieved when the reaction current is 6-8 mA.

5. The synthesis method according to any one of claims 1 to 4, characterized in that: When the quinoxaline compound 1 reacts with the aryl triazene 2, the molar ratio of the quinoxaline compound 1 to the aryl triazene 2 is in the range of 1:1-3, and the optimal ratio is 1:2-3.

6. The synthesis method according to any one of claims 1 to 4, characterized in that: The reaction time is 2-7h, and the optimal reaction time is 3-5h.

7. The synthesis method according to any one of claims 1 to 4, characterized in that: The positive electrode is the C point electrode, the negative electrode is the Ni electrode, and a diaphragm-free electrolytic cell is used for electrochemical reaction.

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