A method for synthesizing pyridine compounds

Abstract

This invention discloses a method for synthesizing pyridine compounds. The method, without the addition of transition metals, photocatalysts, or oxidants, utilizes the direct photolysis of readily available N-methoxypyridine salts to react with various common boron nitrogen salts, phosphine oxides, amides, aldehydes, alkanes, and silanes to obtain various pyridine compounds. Compared with existing technologies, the method for synthesizing pyridine compounds described in this invention features readily available raw materials, simple operation, mild reaction conditions, economy, and environmental friendliness. It has significant application value.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis, specifically relating to a method for synthesizing pyridine compounds. Background Technology

[0002] Pyridine is a six-membered heterocyclic organic compound containing a nitrogen heteroatom and is the most common heterocyclic structural unit in drug molecules. According to incomplete statistics, there are over 180 drugs containing pyridine that have been marketed, and nearly one-fifth of drugs approved for marketing in the last five years contain this structure. Since its discovery in the 1840s, scientists have achieved many important results that benefit mankind through the modification and alteration of pyridine molecules, including well-known herbicides such as paraquat, antitumor drugs such as nilotinib, and antituberculosis drugs such as isoniazid. Furthermore, pyridine compounds are important raw materials in the chemical industry, especially in fine chemicals, with a wide range of applications, including pharmaceutical intermediates, pharmaceutical products, ligands, pesticides, pesticide intermediates, feed and feed ingredients, and many other fields. (J.Med.Chem.2014,57,10257–10274; Angew.Chem.Int.Ed.2017,56,9660–9668; Chem.Rev.2017,117,9302–9332.) Given the importance of functionalized pyridine compounds, the development of efficient pyridine-inducing agents and their successful application in the pyridineization of various organic molecules is particularly important and attracts much attention. Many chemists worldwide are dedicated to research on pyridine-related topics. However, current synthetic methods typically rely on transition metals, oxidants, or photocatalysts, which are insufficient in terms of economy and environmental friendliness. Therefore, finding simple and effective methods to prepare various pyridine compounds from readily available raw materials has always been an important goal of organic synthesis for the better development and application of pyridine compounds. Summary of the Invention

[0003] To address the problems of existing synthetic methods, this invention provides a method for synthesizing pyridine compounds. This method, for the first time, utilizes the direct photolysis of N-methoxypyridine salts, selectively assembling various pyridine compounds using a series of common raw materials, including boron nitrogen salts, unactivated alkanes, phosphine oxides, amides, silanes, and aldehydes. This method provides a simple, efficient, economical, and green synthetic route for pyridine compounds.

[0004] Specifically, in a first aspect, the present invention provides a pyridinizing agent (i.e., an N-methoxypyridinium salt), the structural formula of which is shown in Formula I.

[0005]

[0006] Wherein, R is a substituent on the pyridine ring, which is monosubstituted or polysubstituted, and is independently selected from H, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted aryl, ester group or at least R forming a quinoline structure with the pyridine ring;

[0007] The structural formula of the ester group is -CO2R', where R' is a substituted or unsubstituted C1-C10 alkyl group;

[0008] The substituents in the substituted alkyl group may be selected from: substituted or unsubstituted aryl (preferably phenyl), halogen;

[0009] The substituents in the substituted aryl group can be selected from: halogens, C1-C6 alkyl groups, C1-C6 alkoxy groups, and ester groups;

[0010] Preferably, R represents H, phenyl, C1-C6 alkyl, -CO2 R' where R' is C1-C6 alkyl, C1-C6 alkyl or halogen-substituted phenyl, -CH-(Ph-OCOR”)2 where R” is C1-C6 alkyl;

[0011] X - Selected from p-toluenesulfonyl anion or tetrafluoride borate anion.

[0012] As an example, the compound represented by Formula I is any one of the compounds represented by Formulas I-1 to I-14:

[0013]

[0014] Secondly, the present invention provides the use of the compound shown in Formula I as a pyridinizing agent in the preparation of pyridinized products.

[0015] Thirdly, the method for synthesizing pyridine compounds provided by this invention is the method for synthesizing the compounds shown in Formula IV.

[0016]

[0017]

[0018] In Equation IV, the definition of R is the same as that in Equation I;

[0019] R1, R2, and R3 each independently represent substituted or unsubstituted C1-C10 alkyl groups (preferably C1-C6 alkyl groups), or any two of R1, R2, and R3 form an aza-tri- to six-membered ring (preferably an aza-saturated three- to six-membered ring), specifically a six-membered ring (preferably an aza-saturated six-membered ring).

[0020] The substituents in the substituted C1-C10 alkyl group may be: substituted or unsubstituted aryl (specifically phenyl), halogen;

[0021] The substituents in the substituted aryl group are selected from: halogens, C1-C6 alkyl groups, C1-C6 alkoxy groups, and acyloxy groups;

[0022] Priority, Indicates -NMe3, -NEt3,

[0023] As an example, the compound represented by Formula IV is any one of the compounds represented by Formula IV-1 to Formula IV-13 below:

[0024]

[0025] The method for synthesizing the compound represented by Formula IV provided by this invention includes the following steps:

[0026] Under blue light irradiation, the compound shown in Formula I reacts with the boron-nitrogen salt shown in Formula II via a free radical addition reaction to yield the compound shown in Formula IV.

[0027]

[0028] In Formula II, R1, R2, and R3 each independently represent substituted or unsubstituted C1-C10 alkyl groups, or any two of R1, R2, and R3 form an aza-tri- to six-membered ring, specifically a five-membered ring;

[0029] The substituents in the substituted C1-C10 alkyl group may be substituted or unsubstituted aryl groups or halogens;

[0030] The substituents in the substituted aryl group are selected from: halogen, C1-C6 alkyl, C1-C6 alkoxy, ester group;

[0031] Specifically, R1, R2, and R3 each independently represent methyl, ethyl, butyl, and benzyl; or any two of R1, R2, and R3 form an aza-saturated six-membered ring.

[0032] As an example, the compound represented by Formula II is any one of the compounds represented by Formula II-1 to Formula II-4:

[0033]

[0034] In the above method, the molar ratio of the compound shown in Formula I to the boron nitrogen salt shown in Formula II can be 1:3-1:6, specifically 1:4;

[0035] The reaction is carried out in an organic solvent, specifically acetonitrile.

[0036] The concentration of the compound shown in Formula I in the organic solvent can be 0.1M-0.4M, specifically 0.4M.

[0037] The wavelength of the blue light can be 450nm; the blue light can be provided by a Kessil A160WE LED lamp, and the power of the LED lamp can be 40W.

[0038] The reaction is carried out under alkaline conditions, which may be provided by KH2PO3;

[0039] The molar ratio of KH2PO3 to the compound shown in Formula I can be 1:1-1.5, specifically 1:1;

[0040] The temperature of the free radical addition reaction can be 30–40°C, specifically 35°C; the time can be 10–16 h, specifically 12 h.

[0041] The above method also includes the steps of performing silica gel chromatography separation on the system after the reaction, collecting the sample and then distilling it under reduced pressure; preferably, the stationary phase for silica gel chromatography separation is SiO2; the mobile phase is a mixture of dichloromethane and methanol with a volume ratio of 50:1.

[0042] Fourthly, the present invention also provides a method for synthesizing pyridine compounds, namely compounds represented by formula V.

[0043]

[0044] The method for synthesizing the compound shown in Formula V provided by this invention includes the following steps: under blue light irradiation, the compound shown in Formula I and the compound shown in Formula III undergo a free radical addition reaction to obtain the compound shown in Formula V.

[0045] H-R4

[0046] Formula III,

[0047] In Equation III, R4 represents Wherein, R5 represents a substituted or unsubstituted C1-C10 alkyl group (preferably C2-C6 alkyl group), wherein the substituent is a benzene ring or a halogen, specifically ethylbenzene or dimethylpropyl; or R5 represents a C1-C6 alkyl-substituted amino group (preferably tertiary amino group), specifically dimethylamino or diethylamino.

[0048] Or R4 indicates R6 and R7 each independently represent substituted or unsubstituted aryl groups (specifically, phenyl), wherein the substituents are C1-C6 alkyl, C1-C6 alkoxy, or halogen, specifically phenyl or 3,5-dimethylphenyl;

[0049] or

[0050] R4 indicates Wherein, X is a halogen or a halogen-substituted C1-C6 alkyl group;

[0051] Or X is

[0052] R8 is a C1-C6 alkyl or phenyl group;

[0053] or

[0054] R4 indicates

[0055] or

[0056] R4 indicates a C1-C6 alkyl-substituted silicon group. Among them, R9, R 10 R 11 Each alkyl group independently represents a C1-C10 alkyl group, preferably a C1-C6 alkyl group;

[0057] As an example, the compound represented by Formula III is any one of the compounds represented by Formula III-1 to Formula III-16:

[0058]

[0059]

[0060] In the above method, the molar ratio of the compound shown in Formula I to the compound shown in Formula III can be 1:3-4, specifically 1:4;

[0061] The reaction is carried out in an organic solvent, which may be acetonitrile.

[0062] The concentration of the compound shown in Formula I in the organic solvent can be 0.1M-0.4M, specifically 0.4M;

[0063] The wavelength of the blue light can be 450nm; the blue light can be provided by a Kessil A160WE LED lamp, and the power of the LED lamp can be 40W;

[0064] The temperature of the free radical addition reaction can be 30–40°C, specifically 35°C; the time can be 10–16 h, specifically 12 h.

[0065] The method further includes the steps of performing silica gel chromatography separation on the system after the reaction, collecting the sample and then distilling it under reduced pressure; preferably, the stationary phase for silica gel chromatography separation is SiO2; the mobile phase is a mixture of dichloromethane and methanol in a volume ratio of 50:1.

[0066] As an example, the compound represented by formula V is either the compound represented by formula V-1 or the compound represented by formula V-21.

[0067]

[0068]

[0069] In this invention, those skilled in the art will know that the abbreviations represent the following groups: Me-methyl; Et-ethyl; Bn-benzyl; Ph-phenyl; tBu-tert-butyl.

[0070] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0071] This invention provides a method for synthesizing various pyridine compounds through the direct photolysis of readily available N-methoxypyridine salts, without the addition of transition metals, photocatalysts, or oxidants. The reactions involve the reaction of these compounds with common boron nitrogen salts, phosphine oxides, amides, aldehydes, alkanes, and silanes. Compared to existing technologies, the method for synthesizing pyridine compounds described in this invention offers advantages such as readily available raw materials, simple operation, mild reaction conditions, economy, and environmental friendliness. It has significant application value. Attached Figure Description

[0072] Figure 1 This is the synthetic route for preparing the compound shown in Formula IV according to the present invention.

[0073] Figure 2 The synthetic route for preparing the compound shown in V is provided in this invention. Detailed Implementation

[0074] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0075] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0076] Example 1: Synthesis of the compound shown in Formula I

[0077] The specific steps for synthesizing the compound shown in Formula I are as follows:

[0078] Pyridine oxide (5 mmol) and methyl p-toluenesulfonate (6 mmol) were stirred in acetonitrile (10 mL) overnight at 70 °C. The reaction solvent was evaporated under reduced pressure. The product was recrystallized twice in dichloromethane (15 mL) and diethyl ether (200 mL) at -20 °C to give a white solid product. This was synthesized according to a reported procedure (Angew. Chem. Int. Ed. 2018, 57, 15517–15522).

[0079] Pyridine oxide (5 mmol) and trimethyloxonium tetrafluoroboric acid (6 mmol) were stirred overnight at room temperature in dichloromethane (50 mL). The reaction solvent was evaporated under reduced pressure. The product was recrystallized twice in dichloromethane (15 mL) and diethyl ether (200 mL) at -20 °C to give a white solid product. This was synthesized according to a literature procedure (J. Am. Chem. Soc. 2019, 141, 9239–9248).

[0080] Example 2: Synthesis of the compound shown in Formula IV-1

[0081] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-3 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-1.

[0082]

[0083] The structural verification experimental data are as follows:

[0084] Solid.27mg,0.12mmol,60%yield. 1 H NMR (500MHz, Chloroform-d) δ8.69 (dd, J = 5.2, 0.8Hz, 1H), 7.70–7.62 (m, 3H), 7.52–7.35 (m, 3H), 7.27–7.21 (m, 1H), 2.74 (s, 9H). 13 CNMR(126MHz,Chloroform-d)δ149.2,146.0,139.8,129.5,129.0,128.4,127.2,118.2,52.6. 11 B NMR(160MHz,Chloroform-d)δ-2.6.

[0085] The obtained compound was verified to be the compound shown in Formula IV-1.

[0086] Example 3: Synthesis of the compound shown in Formula IV-2

[0087] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-2. The specific steps are as follows:

[0088] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-1 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-2.

[0089]

[0090] The structural verification experimental data are as follows:

[0091] Solid.21mg,0.13mmol,65%yield. 1 H NMR (400MHz, Chloroform-d) δ8.52 (d, J = 5.1Hz, 1H), 7.30 (s, 1H), 6.95–6.85 (m, 1H), 2.71 (s, 9H), 2.30 (s, 3H). 13 C NMR (101MHz, Chloroform-d) δ147.6,145.9,132.9,121.5,52.6,21.3. 11 B NMR(160MHz,Chloroform-d)δ-2.8.

[0092] The obtained compound was verified to be the compound shown in Formula IV-2.

[0093] Example 4: Synthesis of the compound shown in Formula IV-3

[0094] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-3. The specific steps are as follows:

[0095] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-2 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-3.

[0096]

[0097] The structural verification experimental data are as follows:

[0098] Yellow oil.26mg,0.12mmol,62%yield. 1 H NMR (500MHz, Chloroform-d) δ8.53 (d, J = 5.3, 1H), 7.42 (s, 1H), 7.02–6.95 (m, 1H), 2.72 (s, 9H), 1.28 (s, 9H). 13 C NMR (126MHz, Chloroform-d) δ157.0,148.7,128.1,117.0,52.5,34.4,30.8. 11 B NMR(160MHz,CHLOROFORM-D)δ-2.4.IR(ATR):2963,2869,2327,2276,1619,1535,1461,1395,1196,1144,1103,881,842,807,558,441cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 12 H 24 BN2 + :207.2027; found 207.2025.

[0099] The obtained compound was verified to be the compound shown in Formula IV-3.

[0100] Example 5: Synthesis of the compound shown in Formula IV-4

[0101] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-4. The specific steps are as follows:

[0102] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-3 (0.2 mmol) and triethylamine-borane shown in Formula II-2 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-4.

[0103]

[0104] The structural verification experimental data are as follows:

[0105] Solid.28mg,0.11mmol,52%yield.Melting Point:150-151℃. 1 H NMR (400MHz, Chloroform-d) δ8.66(d,J=5.1Hz,1H),7.75–7.60(m,3H),7.50–7.35(m,3H),7.25–7.15(m,1H),3.10–3.00(m,6H),1.22(t,J=7.2Hz,9H). 13 C NMR (101MHz, Chloroform-d) δ149.2,145.6,140.0,128.9,128.8,128.3,127.2,117.8,50.2,8.5. 11 B NMR(160MHz,Chloroform-d)δ-8.5.IR(ATR):2919,2851,2381,2263,1879,1619,1532,1467,1387,1136,1107,1086,752,695,495cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 17 H 26 BN2 + :269.2184; found 269.2182.

[0106] The obtained compound was verified to be the compound shown in Formula IV-4.

[0107] Example 6: Synthesis of the compound shown in Formula IV-5

[0108] according to Figure 1The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-5. The specific steps are as follows:

[0109] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-4 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-5.

[0110]

[0111] The structural verification experimental data are as follows:

[0112] White wax.30mg,0.10mmol,50%yield. 1 H NMR (400MHz, Chloroform-d) δ8.81–8.46(m,1H),7.70–7.60(m,4H),7.60–7.37(m,2H),2.76(s,9H). 13 C NMR (126MHz, Chloroform-d) δ149.3,132.1,129.0,128.8,128.4,127.2,118.1,117.7,52.6. 11 B NMR(160MHz,Chloroform-d)δ-3.6.IR(ATR):2989,2926,2379,1617,1469,1140,1108,1086,843,803,761,692,498cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 14 H 19 BBrN2 + :305.0819; found305.0816.

[0113] The obtained compound was verified to be the compound shown in Formula IV-5.

[0114] Example 7: Synthesis of the compound shown in Formula IV-6

[0115] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-6. The specific steps are as follows:

[0116] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-5 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-6.

[0117]

[0118] The structural verification experimental data are as follows:

[0119] Solid.21mg,0.10mmol,51%yield.Melting Point:151-152℃. 1 H NMR (500MHz, Chloroform-d) δ8.79–8.75(m,1H),7.93(d,J=4.3Hz,1H),7.54–7.50(m,1H),3.91(s,3H),2.73(s,9H). 13 C NMR (101MHz, Chloroform-d) δ167.5,149.5,134.8,129.7,118.8,52.6,52.5. 11 B NMR(160MHz,Chloroform-d)δ-3.9.IR(ATR):2967,2349,1728,1660,1620,1383,1302,1253,1087,917,761,705,477cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 10 H 18 BN2O2 + :209.1456; found 209.1455.

[0120] The obtained compound was verified to be the compound shown in Formula IV-6.

[0121] Example 8: Synthesis of the compound shown in Formula IV-7

[0122] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-7. The specific steps are as follows:

[0123] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-11 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-7.

[0124]

[0125] The structural verification experimental data are as follows:

[0126] Solid.22mg,0.10mmol,52%yield. 1 H NMR(500MHz,Chloroform-d)δ8.09–8.04(m,1H),7.94–7.88(m,1H),7.62–7.56(m,1H),7.46–7.40(m,1H),7.33(s,1H),2.88(s,9H)2.62(s,3H). 13 C NMR (126MHz, Chloroform-d) δ148.1,139.6,129.9,129.3,127.7,126.5,124.5,123.6,52.6,18.6. 11 B NMR(160MHz,Chloroform-d)δ-3.4.

[0127] The obtained compound was verified to be the compound shown in Formula IV-7.

[0128] Example 9: Synthesis of the compound shown in Formula IV-8

[0129] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-8. The specific steps are as follows:

[0130] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-3 (0.2 mmol) and the boron nitrogen salt shown in Formula II-3 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, and the mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-8.

[0131]

[0132] The structural verification experimental data are as follows:

[0133] Solid.27mg,0.10mmol,51%yield.Melting Point:148-149℃. 1 H NMR(400MHz,Chloroform-d)δ8.70(d,J=5.2Hz,1H),7.72–7.63(m,3H),7.46–7.37(m,3H),7.24(dd,J=5.3,2.1Hz ,1H),3.26–3.16(m,2H),2.96–2.86(m,2H),2.73(s,3H),1.85–1.75(m,2H),1.75–1.60(m,3H),1.55–1.40(m,1H). 13 C NMR (101MHz, Chloroform-d) δ149.2,145.9,139.8,129.8,129.0,128.4,127.2,118.1,58.5,45.8,22.9,20.3. 11 B NMR(160MHz,Chloroform-d)δ-4.0.IR(ATR):2929,2851,2381,2263,1997,1618,1467,1135,1106,1077,744,699,554,492cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 17 H 24 BN2 + :267.2027; found267.2026.

[0134] The obtained compound was verified to be the compound shown in Formula IV-8.

[0135] Example 10: Synthesis of the compound shown in Formula IV-9

[0136] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-9. The specific steps are as follows:

[0137] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-3 (0.2 mmol) and dimethylbenzylamine-borane shown in Formula II-4 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-9.

[0138]

[0139] The structural verification experimental data are as follows:

[0140] Solid.29mg,0.10mmol,48%yield.Melting Point:137-138℃. 1 H NMR(500MHz,Chloroform-d)δ8.74(d,J=5.2Hz,1H),7.74(d,J=2.0Hz,1H),7.71–7.64(m,2H),7.4 9–7.44(m,2H),7.42–7.36(m,4H),7.35–7.29(m,2H),7.29–7.25(m,1H),4.26(s,2H),2.62(s,6H). 13 C NMR (101MHz, Chloroform-d) δ149.4,148.1,145.8,139.9,132.6,129.5,129.1,129.0,128.9,128.5,128.4,127.2,123.1,118.1,65.7,48.0. 11 B NMR(160MHz,Chloroform-d)δ-2.9.IR(ATR):2958,2925,2383,1725,1619,1467,1268,1136,1075,752,695,496cm - 1 .HRMS(ESI):m / z[M+H] + calcd for C20 H 24 BN2 + :303.2027; found 303.2021.

[0141] The obtained compound was verified to be the compound shown in Formula IV-9.

[0142] Example 11: Synthesis of the compound shown in Formula IV-10

[0143] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-10. The specific steps are as follows:

[0144] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-6 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-10.

[0145]

[0146] The structural verification experimental data are as follows:

[0147] Solid.19mg,0.11mmol,53%yield. 1 H NMR(500MHz,Chloroform-d)δ7.06(s,2H),2.56(s,9H),2.48(s,6H). 13 C NMR(126MHz,Chloroform-d)δ155.5,129.5,52.3,24.4. 11 BNMR(160MHz,Chloroform-d)δ-2.0.

[0148] The obtained compound was verified to be the compound shown in Formula IV-10.

[0149] Example 12, Synthesis of the compound shown in Formula IV-11

[0150] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-11. The specific steps are as follows:

[0151] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-12 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-11.

[0152]

[0153] The structural verification experimental data are as follows:

[0154] Solid.26mg,0.12mmol,60%yield. 1 H NMR (500MHz, Chloroform-d) δ8.56(d,J=8.5,1H),7.98(d,J=8.4,1H),7.62–7.54(m,1H),7.46(s,1H),7.44–7.38(m,1H),2.71(s,3H),2.60(s,9H). 13 C NMR (126MHz, Chloroform-d) δ157.5,147.9,132.9,132.3,129.1,129.0,128.1,124.4,52.9,25.4. 11 B NMR(160MHz,Chloroform-d)δ-4.3

[0155] Upon verification, the obtained compound is the compound shown in Formula IV-11.

[0156] Example 13, Synthesis of the compound shown in Formula IV-12

[0157] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-12. The specific steps are as follows:

[0158] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-14 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-12.

[0159]

[0160] The structural verification experimental data are as follows:

[0161] Solid.Yield: (49mg, 0.11mmol, 57%). 1 H NMR (500MHz, Chloroform-d) δ8.41 (d, J = 4.7, 1H), 7.25–7.16 (m, 6H), 7.01–6.90 (m, 4H), 5.61 (s, 1H), 2.48 (s, 9H), 2.27 (s, 6H). 13 CNMR(126MHz,Chloroform-d)δ169.7,160.6,149.2,148.0,141.0,133.0,130.7,130.4,130.2,121.3,58.2,52.1,21.3. 11 B NMR(160MHz,Chloroform-d)δ-2.9.IR(ATR):2926,2170,1754,1599,1504,1368,1196,1164,1016,911,838,660,511cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 25 H 30 BN2O4 + :433.2293; found 433.2292.

[0162] Upon verification, the obtained compound is the compound shown in Formula IV-12.

[0163] Example 14, Synthesis of the compound shown in Formula IV-13

[0164] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula IV-13. The specific steps are as follows:

[0165] The pre-dried reaction tube was cooled to room temperature under vacuum, and KH₂PO₃ (0.2 mmol) was added. Under nitrogen protection, the compound shown in Formula I-13 (0.2 mmol) and trimethylamine-borane shown in Formula II-1 (0.8 mmol) were added. Acetonitrile (0.5 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO₂, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula IV-13.

[0166]

[0167] The structural verification experimental data are as follows:

[0168] Solid.25mg,0.11mmol,53%yield. 1 H NMR(500MHz,)δ7.38–7.32(m,1H),7.26–7.24(m,4H),7.21–7.12(m,2H),6.81(dd,J=7.7,1.2Hz,1H),4.16(s,2H),2.69(s,9H). 13 CNMR(126MHz,Chloroform-d)δ159.2,141.1,134.3,129.4,128.4,128.2,126.0,119.0,52.5,45.3. 11 B NMR(160MHz,Chloroform-d)δ-4.1.IR(ATR):3026,2995,2938,2334,1559,1486,1439,1254,1160,1125,1073,988,845,762,698,566,463cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 15 H 22 BN2 + :241.1871; found 241.1870.

[0169] The obtained compound was verified to be the compound shown in Formula IV-13.

[0170] Example 15: Synthesis of the compound shown in Formula V-1

[0171] according to Figure 1The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-1. The specific steps are as follows:

[0172] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-9 (0.1 mmol) and the aldehyde shown in Formula III-1 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-1.

[0173]

[0174] The structural verification experimental data are as follows:

[0175] White solid.19mg,0.065mmol,65%yield. 1 H NMR(400MHz,Chloroform-d)δ8.12–8.02(m,2H),7.99(dd,J=7.1,1.6Hz,1H),7.96–7.85(m,2H),7.55–7. 41(m,3H),7.35–7.24(m,4H),7.29–7.16(m,1H),3.69(dd,J=8.3,7.2Hz,2H),3.12(dd,J=8.3,7.2Hz,2H). 13 C NMR (101MHz, Chloroform-d) δ201.6,156.6,153.2,141.8,138.5,137.9,129.6,129.0,128.7,128.6,127.1,126.1,123.7,120.2,39.7,30.3.

[0176] Upon verification, the obtained compound is the compound shown in Formula V-1.

[0177] Example 16: Synthesis of the compound shown in Formula V-2

[0178] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-2. The specific steps are as follows:

[0179] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-9 (0.1 mmol) and the aldehyde shown in Formula III-2 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-2.

[0180]

[0181] The structural verification experimental data are as follows:

[0182] Yellow oil.13mg,0.06mmol,55%yield. 1 H NMR(400MHz,Chloroform-d)δ8.14–8.02(m,2H),8.02–7.84(m,3H),7.59–7.43(m ,3H),3.22(d,J=6.9Hz,2H),2.37(dq,J=13.5,6.7Hz,1H),1.04(d,J=6.7Hz,6H). 13 C NMR(101MHz,Chloroform-d)δ202.4,156.4,153.6,138.6,137.8,129.5,129.0,127.0,123.4,120.1,46 .6,25.1,23.0.IR(ATR):2955,2926,2870,1693,1578,1447,1365,1311,1214,1012,814,761,692,623cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 16 H 18 ON + 240.1383; found 240.1379.

[0183] Upon verification, the obtained compound is the compound shown in Formula V-2.

[0184] Example 17: Synthesis of the compound shown in Formula V-3

[0185] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-3. The specific steps are as follows:

[0186] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-10 (0.1 mmol) and the aldehyde shown in Formula III-1 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-3.

[0187]

[0188]

[0189] The structural verification experimental data are as follows:

[0190] Yellow wax.18mg,0.06mmol,60%yield. 1 H NMR(500MHz,Chloroform-d)δ8.03–7.93(m,3H),7.92–7.83(m,2H),7.36–7.28(m,6H),7.2 4–7.17(m,1H),3.70–3.66(dd,J=8.3,7.2Hz,2H),3.11(dd,J=8.3,7.2Hz,2H),2.43(s,3H). 13 C NMR(126MHz,Chloroform-d)δ201.7,156.6,153.1,141.8,139.7,137.7,135.7,129.7,128.7,128.6,126.9,126.1,123. 3,119.8,39.7,30.3,21.4.IR(ATR):2919,2852,2349,1694,1584,1495,1450,1362,1310,1072,982,802,771,698,464cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 21 H 20 ON + :302.1539; found 302.1535.

[0191] The obtained compound was verified to be the compound shown in formula V-3.

[0192] Example 18: Synthesis of the compound shown in V-4

[0193] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-4. The specific steps are as follows:

[0194] The pre-dried reaction tube was lowered to room temperature under vacuum, and the compound shown in Formula I-3 (0.1 mmol) was added under nitrogen protection. The amide shown in Formula III-3 (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure. Separation was performed using a silica gel column with SiO2 as the stationary phase and a 50:1 (v / v) mixture of dichloromethane and methanol as the mobile phase. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-4.

[0195]

[0196] The structural verification experimental data are as follows:

[0197] Yellow oil.15mg,0.07mmol,67%yield. 1 H NMR (500MHz, Chloroform-d) δ8.63(dd,J=5.2,0.9Hz,1H),7.87(dd,J=1.9,0.8Hz,1H),7.69–7.63(m,2H),7.60–7.36(m,4H),3.17(s,3H),3.12(s,3H). 13 C NMR(126MHz,Chloroform-d)δ169.3,155.2,149.7,148.9,137.7,129.6,129.4,127.2,122.4,1 21.7,39.3,35.9.IR(ATR):2927,2349,1630,1594,1499,1376,1092,1052,761,695,613,480cm -1 .HRMS(ESI):m / z[M+H] + calcd forC 14 H 15 ON2 + :227.1179; found 227.1176.

[0198] The obtained compound was verified to be the compound shown in Formula V-4.

[0199] Example 19: Synthesis of the compound shown in Formula V-5

[0200] according to Figure 1The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-5. The specific steps are as follows:

[0201] The pre-dried reaction tube was lowered to room temperature under vacuum, and the compound shown in Formula I-9 (0.1 mmol) was added under nitrogen protection. The amide shown in Formula III-3 (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure. Separation was performed using a silica gel column with SiO2 as the stationary phase and a 50:1 (v / v) mixture of dichloromethane and methanol as the mobile phase. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-5.

[0202]

[0203] The structural verification experimental data are as follows:

[0204] Yellow oil.16mg,0.07mmol,70%yield. 1 H NMR(500MHz,Chloroform-d)δ8.06–7.99(m,2H),7.88–7.82(m,1H),7.77(d,J= 7.9Hz,1H),7.61(d,J=7.6Hz,1H),7.53–7.38(m,3H),3.20(s,3H),3.18(s,3H). 13 C NMR (101MHz, Chloroform-d) δ169.1,155.9,154.4,138.9,137.9,129.4,128.9,127.1,122.2,121.1,39.4,36.1.

[0205] The obtained compound was verified to be the compound shown in Formula V-5.

[0206] Example 20: Synthesis of the compound shown in Formula V-6

[0207] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-6. The specific steps are as follows:

[0208] The pre-dried reaction tube was lowered to room temperature under vacuum, and the compound shown in Formula I-9 (0.1 mmol) was added under nitrogen protection. The amide shown in Formula III-4 (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under 40 W blue LED (450 nm) illumination. The reaction solution was distilled under reduced pressure. Separation was performed using a silica gel column with SiO2 as the stationary phase and a 50:1 (v / v) mixture of dichloromethane and methanol as the mobile phase. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-6.

[0209]

[0210] The structural verification experimental data are as follows:

[0211] Yellow oil.15mg,0.06mmol,60%yield. 1 H NMR (400MHz, Chloroform-d) δ8.08–7.98(m,2H),7.87–7.63(m,2H),7.59–7.38(m,4H),3.59(q,J=7.0Hz,2H),3.48(q,J=7.0Hz,2H),1.35–1.15(m,6H). 13 C NMR (101MHz, Chloroform-d) δ168.7,155.9,155.1,139.0,137.8,129.3,128.9,127.2,121.9,120.9,43.5,40.5,14.7,13.0.

[0212] Upon verification, the obtained compound is the compound shown in Formula V-6.

[0213] Example 21: Synthesis of the compound shown in Formula V-7

[0214] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-7. The specific steps are as follows:

[0215] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-3 (0.1 mmol) was added under nitrogen protection. The amide shown in Formula III-5 (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm). The reaction solution was distilled under reduced pressure. Separation was performed using a silica gel column with SiO2 as the stationary phase and a 50:1 (v / v) mixture of dichloromethane and methanol as the mobile phase. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-7.

[0216]

[0217] The structural verification experimental data are as follows:

[0218] Yellow oil.20mg,0.09mmol,85%yield. 1 H NMR (500MHz, Chloroform-d) δ8.57(d,J=5.2Hz,1H),7.66–7.58(m,4H),7.51–7.45(m,3H),4.77(s,2H),3.08(s,3H),2.18(s,3H). 13 C NMR (126MHz, Chloroform-d) δ171.5,171.0,158.1,157.4,150.5,149.9,149.7,149.5,138.2,137.9,129.5,129.3,129.2,127.2,127.2,120. 8,120.6,120.3,118.2,56.4,53.0,36.6,34.4,22.0,21.7.IR(ATR):29 27,2349,1633,1595,1545,1474,1396,1240,1023,844,762,696,595cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 15 H 17 ON2 + :241.1335; found241.1334.

[0219] Upon verification, the obtained compound is the compound shown in Formula V-7.

[0220] Example 22: Synthesis of the compound shown in Formula V-8

[0221] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-8. The specific steps are as follows:

[0222] The pre-dried reaction tube was cooled to room temperature under vacuum, and compound I-7 (0.1 mmol) and phosphine oxide (0.3 mmol) of formula III-6 were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain compound V-8.

[0223]

[0224] The structural verification experimental data are as follows:

[0225] White solid.Yield:20mg,0.07mmol,70%yield. 1 H NMR (500MHz, Chloroform-d) δ8.75 (dt, J=5.6, 2.7Hz, 2H), 7.69–7.62 (m, 4H), 7.62–7.35 (m, 8H). 13 C NMR(126MHz,Chloroform-d)δ150.1(d,J CP =9.6Hz), 142.2(d,J CP =96.7Hz), 132.7(d,J) CP =2.9Hz), 132.1(d,J CP =10.1Hz), 131.0(d,J CP =105.4Hz), 129.0(d,J) CP =12.3Hz), 125.9(d,J) CP =7.9Hz).

[0226] Upon verification, the obtained compound is the compound shown in Formula V-8.

[0227] Example 23: Synthesis of the compound shown in Formula V-9

[0228] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-9. The specific steps are as follows:

[0229] The pre-dried reaction tube was cooled to room temperature under vacuum, and compound I-8 (0.1 mmol) and phosphine oxide (0.3 mmol) of formula III-6 were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain compound V-9.

[0230]

[0231] The structural verification experimental data are as follows:

[0232] White solid.25mg,0.09mmol,85%yield. 1 H NMR (400MHz, Chloroform-d) δ8.65–8.55(m,1H),7.75–7.55(m,6H),7.53–7.44(m,6H),2.58(s,3H). 13 C NMR(101MHz,Chloroform-d)δ159.2(d,J CP =9.8Hz), 149.3(d,J CP =10.3Hz), 142.3(d,J CP =96.8Hz), 132.6(d,J) CP =2.8Hz), 132.1(d,J CP =10.1Hz), 131.1(d,J CP =105.2Hz), 128.9(d,J) CP =12.4Hz), 125.5(d,J) CP =7.8Hz), 122.8(d,J CP =8.6Hz), 24.7.

[0233] Upon verification, the obtained compound is the compound shown in Formula V-9.

[0234] Example 24: Synthesis of the compound shown in Formula V-10

[0235] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-10. The specific steps are as follows:

[0236] The pre-dried reaction tube was cooled to room temperature under vacuum, and compound I-6 (0.1 mmol) and phosphine oxide (0.3 mmol) of formula III-6 were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain compound V-10.

[0237]

[0238] The structural verification experimental data are as follows:

[0239] Yellow oil.20mg,0.07mmol,65%yield. 1H NMR (400MHz, Chloroform-d) δ7.68–7.61(m,4H),7.61–7.54(m,2H),7.54–7.39(m,4H),7.20(d,J=12.0Hz,2H),2.53(s,6H). 13 CNMR(101MHz,Chloroform-d)δ158.5(d,J CP =10.4Hz), 142.3(d,J CP =97.0Hz), 132.5(d,J CP =2.8Hz), 132.1(d,J CP =10.0Hz), 131.3(d,J CP =104.9Hz), 128.9(d,J) CP =12.3Hz), 122.3(d,J CP =8.1Hz).24.8.

[0240] Upon verification, the obtained compound is the compound shown in Formula V-10.

[0241] Example 25: Synthesis of the compound shown in Formula V-11

[0242] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-11. The specific steps are as follows:

[0243] The pre-dried reaction tube was cooled to room temperature under vacuum, and compound I-8 (0.1 mmol) and phosphine oxide (0.3 mmol) of formula III-7 were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain compound V-11.

[0244]

[0245] The structural verification experimental data are as follows:

[0246] Colorless oil.19mg,0.06mmol,57%yield. 1H NMR (500MHz, Chloroform-d) δ8.62–8.57(m,1H),7.50(d,J=12.1Hz,1H),7.40–7.34(m,1H),7.26–7.15(m,6H),2.59(s,3H),2.32(s,12H). 13 C NMR(126MHz,Chloroform-d)δ159.1(d,J CP =9.6Hz), 149.2(d,J CP =10.3Hz), 142.8(d,J) CP =95.9Hz), 138.6(d,J) CP =13.0Hz), 134.3(d,J CP =2.9Hz), 134.2, 131.0(d,J) CP =104.2Hz), 129.6(d,J) CP =10.1Hz),128.94,128.87125.5(d,J CP =7.6Hz), 122.9(d,J CP =8.1Hz), 24.8, 21.5. 31 P NMR(202MHz,Chloroform-d)δ28.4.IR(ATR):2919,2349,2219,1587,1444,1416,1379,1273,1183,1125,1041,850,728,690,590,576,477cm - 1 .HRMS(ESI):m / z[M+H] + calcd for C 22 H 25 ONP + 350.1668; found 350.1662.

[0247] Upon verification, the obtained compound is the compound shown in Formula V-11.

[0248] Example 26: Synthesis of the compound shown in Formula V-12

[0249] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-12. The specific steps are as follows:

[0250] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the ester shown in Formula III-8 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated using a silica gel column. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-12.

[0251]

[0252] The structural verification experimental data are as follows:

[0253] Colorless oil.10mg,0.06mmol,60%yield. 1 H NMR(500MHz,Chloroform-d)δ8.40(d,J=5.3Hz,1H),7.08(d,J=1.9Hz,1H),7.04–7.01(m,1H),4.06(q ,J=7.1Hz,2H),2.54(s,3H),2.09–2.00(m,2H),2.00–1.90(m,2H),1.29(s,6H),1.21(t,J=7.1Hz,3H). 13 CNMR(101MHz,Chloroform-d)δ173.7,158.5,157.7,149.3,120.8,118.5,60.6,38.3,37.4,30.2 ,28.1,24.8,14.3.IR(ATR):2967,2350,1731,1600,1549,1394,1298,1182,1025,832,618,450cm -1 .HRMS(ESI):m / z[M+H] + calcd for C 14 H 22 O2N + :236.1645; found 236.1641.

[0254] Upon verification, the obtained compound is the compound shown in Formula V-12.

[0255] Example 27: Synthesis of the compound shown in Formula V-13

[0256] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-13. The specific steps are as follows:

[0257] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the ester shown in Formula III-8 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-13.

[0258]

[0259] The structural verification experimental data are as follows:

[0260] Colorless oil.17mg,0.06mmol,57%yield. 1 H NMR(500MHz,Chloroform-d)δ8.62(d,J=5.3Hz,1H),8.03–7.94(m,2H),7.67–7.64(m,1H),7.61–7.37(m,3H ),7.20(dd,J=5.3,1.9Hz,1H),4.05(q,J=7.1Hz,2H),2.16–1.97(m,4H),1.37(s,6H),1.20(t,J=7.1Hz,3H). 13 C NMR (126MHz, Chloroform-d) δ173.7,157.8,149.8,139.8,129.1,128.9,127.2,120.0,118.5,60.6,38.3,37.7,30.2,28.2,14.3.

[0261] Upon verification, the obtained compound is the compound shown in formula V-13.

[0262] Example 28: Synthesis of the compound shown in Formula V-14

[0263] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-14. The specific steps are as follows:

[0264] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the ester shown in Formula III-9 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, while the mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-14.

[0265]

[0266] The structural verification experimental data are as follows:

[0267] Colorless oil.20mg,0.05mmol,59%yield. 1 H NMR(400MHz,Chloroform-d)δ8.60(d,J=5.3Hz,1H),7.98–7.91(m,2H),7.85–7.78(m,2H),7.72–7.69(m,1H ),7.58–7.31(m,6H),7.24(dd,J=5.3,1.9Hz,1H),4.25(t,J=7.0Hz,2H),2.22(t,J=7.0Hz,2H),1.46(s,6H). 13 C NMR(101MHz,Chloroform-d)δ166.6,158.5,157.9,149.9,139.9,133.0,130 .1,129.5,128.9,128.8,128.4,127.2,119.7,118.2,62.1,41.9,37.0,28.7.

[0268] Upon verification, the obtained compound is the compound shown in Formula V-14.

[0269] Example 29: Synthesis of the compound shown in Formula V-15

[0270] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-15. The specific steps are as follows:

[0271] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the chloroalkane shown in Formula III-10 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, and the mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-15.

[0272]

[0273] The structural verification experimental data are as follows:

[0274] Colorless oil.13mg,0.05mmol,51%yield. 1 H NMR(500MHz,Chloroform-d)δ8.63(d,J=5.3Hz,1H),8.01–7.94(m,2H),7.65(d,J=1.9Hz,1H),7.52–7.46( m,2H),7.47–7.36(m,1H),7.19(dd,J=5.3,1.8Hz,1H),3.33–3.26(m,2H),2.24–2.17(m,2H),1.40(s,6H). 13 C NMR (126MHz, Chloroform-d) δ158.1,157.6,150.1,139.8,129.1,128.9,127.2,119.6,118.1,46.7,40.8,38.1,28.4.

[0275] Upon verification, the obtained compound is the compound shown in Formula V-15.

[0276] Example 30: Synthesis of the compound shown in Formula V-16

[0277] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-16. The specific steps are as follows:

[0278] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the bromoalkane shown in Formula III-11 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, and the mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-16.

[0279]

[0280] The structural verification experimental data are as follows:

[0281] Colorless oil.18mg,0.05mmol,53%yield. 1 H NMR(400MHz,Chloroform-d)δ8.61(d,J=5.3Hz,1H),8.01–7.94(m,2H),7.67–7.64(m,1H),7.54–7.38 (m,3H),7.19(dd,J=5.3,1.8Hz,1H),3.33(s,2H),1.87–1.78(m,2H),1.65–1.57(m,2H),1.37(s,6H). 13 C NMR (101MHz, Chloroform-d) δ158.7,157.8,149.8,140.0,128.9,128.8,127.2,119.9,118.3,42.3,37.8,34.3,28.4,28.2.

[0282] Upon verification, the obtained compound is the compound shown in Formula V-16.

[0283] Example 31: Synthesis of the compound shown in Formula V-17

[0284] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-17. The specific steps are as follows:

[0285] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the alkane shown in Formula III-12 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-17.

[0286]

[0287] The structural verification experimental data are as follows:

[0288] Colorless oil.13mg,0.05mmol,53%yield. 1 H NMR(500MHz,Chloroform-d)δ8.59(d,J=5.3Hz,1H),7.99–7.94(m,2H),7.66(d,J=1.8Hz,1H),7.51–7.45(m ,2H),7.44–7.38(m,1H),7.19(dd,J=5.3,1.8Hz,1H),2.02–1.93(m,1H),1.29(s,6H),0.81(d,J=6.8Hz,6H). 13 C NMR (126MHz, Chloroform-d) δ160.3,157.4,149.5,140.2,128.84,128.82,128.77,127.2,120.4,118.8,41.0,37.9,24.3,18.0.

[0289] Upon verification, the obtained compound is the compound shown in Formula V-17.

[0290] Example 32: Synthesis of the compound shown in Formula V-18

[0291] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-18. The specific steps are as follows:

[0292] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the alkane shown in Formula III-13 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-18.

[0293]

[0294] The structural verification experimental data are as follows:

[0295] Colorless oil.18mg,0.07mmol,65%yield. 1 H NMR(500MHz,Chloroform-d)δ8.60(d,J=5.3Hz,1H),8.03–7.92(m,2H),7.73–7.69(m,1H),7.52–7.45(m,2H),7.44–7.36(m,1H),7 .25(dd,J=5.3,1.9Hz,1H),1.88–1.69(m,5H),1.32(d,J=0.8Hz,3H),1.22–1.12(m,2H),0.95(d,J=6.2Hz,6H),0.67–0.50(m,1H). 13 C NMR (126MHz, Chloroform-d) δ162.2,157.7,149.7,140.3,128.9,128.8,127.2,119.4,117.8,45.8,43.9,38.8,28.3,25.2,23.0.

[0296] Upon verification, the obtained compound is the compound shown in formula V-18.

[0297] Example 33: Synthesis of the compound shown in Formula V-19

[0298] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-19. The specific steps are as follows:

[0299] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the alkane shown in Formula III-14 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-19.

[0300]

[0301] The structural verification experimental data are as follows:

[0302] Yellow oil.15mg,0.05mmol,53%yield. 1 H NMR(500MHz,Chloroform-d)δ8.61(d,J=5.3Hz,1H),7.97(dd,J=7.5,1.8Hz,2H),7.68(d,J=1.8Hz,1H),7.47(t,J=7.5Hz ,2H),7.41(dd,J=8.3,6.1Hz,1H),7.21(dd,J=5.3,1.8Hz,1H),2.16–2.12(m,3H),1.99–1.93(m,6H),1.87–1.73(m,6H). 13 C NMR (126MHz, Chloroform-d) δ160.9,157.7,149.7,140.2,128.8,127.2,119.1,117.6,42.6,36.7,28.8.

[0303] Upon verification, the obtained compound is the compound shown in Formula V-19.

[0304] Example 34: Synthesis of the compound shown in Formula V-20

[0305] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-20. The specific steps are as follows:

[0306] The pre-dried reaction tube was cooled to room temperature under vacuum, and the compound shown in Formula I-8 (0.1 mmol) and the alkane shown in Formula III-15 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain the compound shown in Formula V-20.

[0307]

[0308] The structural verification experimental data are as follows:

[0309] Colorless oil.21mg,0.07mmol,65%yield. 1 H NMR(500MHz,Chloroform-d)δ8.60(d,J=5.3Hz,1H),8.00–7.95(m,2H),7.67(d,J=1.8Hz,1H),7.48(dd,J=8.3,6.8Hz,2H),7.44–7.37(m,1H ),7.21(dd,J=5.3,1.8Hz,1H),2.26–2.20(m,1H),1.82–1.74(m,2H),1.65–1.49(m,4H),1.48–1.40(m,4H),1.30–1.18(m,2H),0.91(s,6H). 13 C NMR (126MHz, Chloroform-d) δ160.3,157.7,149.7,140.2,128.8,128.8,127.2,119.2,117.7,50.8,48.9,42.9,41.2,38.5,31.6,30.8,29.9.

[0310] Upon verification, the obtained compound is the compound shown in Formula V-20.

[0311] Example 35: Synthesis of the compound shown in Formula V-21

[0312] according to Figure 1 The synthetic route diagram shown illustrates the synthesis of the compound represented by formula V-21. The specific steps are as follows:

[0313] The pre-dried reaction tube was cooled to room temperature under vacuum, and compound I-8 (0.1 mmol) and silane III-16 (0.3 mmol) were added under nitrogen protection. Acetonitrile (0.25 mL) was added to the mixture via syringe. The mixture was stirred overnight (12 h) at 35 °C under irradiation with a 40 W blue LED (450 nm) lamp. The reaction solution was distilled under reduced pressure, and the stationary phase was SiO2, separated by silica gel column chromatography. The mobile phase was a mixture of dichloromethane and methanol in a volume ratio of 50:1. The eluent was collected and distilled under reduced pressure to finally obtain compound V-21.

[0314]

[0315] The structural verification experimental data are as follows:

[0316] Colorless oil.14mg,0.05mmol,53%yield. 1 H NMR(500MHz,Chloroform-d)δ8.65(d,J=4.7Hz,1H),8.04–7.94(m,2H),7.80(s,1H),7 .52–7.46(m,2H),7.45–7.39(m,1H),7.33(d,J=4.7Hz,1H),0.92(s,9H),0.34(s,6H). 13 C NMR (126MHz, Chloroform-d) δ156.2,148.8,148.4,140.0,128.9,128.9,127.9,127.2,126.3,26.5,16.9,-6.4.

[0317] Upon verification, the obtained compound is the compound shown in formula V-21.

[0318] The present invention has been described in detail above. Those skilled in the art will recognize that the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope, and without requiring unnecessary experiments. While specific embodiments have been provided, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including changes made using conventional techniques known in the art that depart from the scope disclosed herein.

Claims

1. A method for synthesizing the compound shown in formula V-A, ， In formula V-A, R is a substituent on the pyridine ring, which can be monosubstituted or polysubstituted, and R can be hydrogen, phenyl, methyl, or methyl-substituted phenyl. R4 indicates ,in, R5 represents a substituted or unsubstituted C1-C10 alkyl group, wherein the substituent is a benzene ring or a halogen; or R5 represents an amino group substituted by a C1-C6 alkyl group. Or R4 indicates ; The method includes the following steps: under blue light irradiation, the compound shown in Formula I and the compound shown in Formula III undergo a free radical addition reaction to obtain the compound shown in Formula V-A; The definition of R in equation I is the same as the definition of R in equation V-A, X - Selected from p-toluenesulfonic acid anion or tetrafluoride borate anion; ， In Equation III, the definition of R4 is the same as that in Equation V-A; The free radical addition reaction uses acetonitrile as an organic solvent and is carried out under 40W blue LED light at 30-40°C.

2. The method for synthesizing the compound shown in formula V-B, ， In formula V-B, R is a substituent on the pyridine ring, which can be monosubstituted or polysubstituted, and R can be hydrogen, phenyl, methyl, or methyl-substituted phenyl. R4 indicates ,in, R6 and R7 are independently substituted or unsubstituted aryl groups, wherein the substituents are C1-C6 alkyl, C1-C6 alkoxy, or halogen; Or R4 indicates Wherein, X is a halogen, a halogen-substituted C1-C6 alkyl group, or X is... or R8 is a C1-C6 alkyl or phenyl group; Or R4 indicates ; Or R4 indicates Among them, R9, R 10 R 11 Each can be independently represented as a C1-C10 alkyl group; The method includes the following steps: under blue light irradiation, the compound shown in Formula I and the compound shown in Formula III undergo a free radical addition reaction to obtain the compound shown in Formula V-B; The definition of R in equation I is the same as the definition of R in equation V-B, X - Selected from p-toluenesulfonic acid anion or tetrafluoride borate anion; ， In Equation III, the definition of R4 is the same as that in Equation V-B; The free radical addition reaction uses acetonitrile as an organic solvent and is carried out under 40W blue LED light at 30-40°C.

3. The method according to claim 1 or 2, characterized in that: The molar ratio of the compound shown in Formula I to the compound shown in Formula III is 1:3-4; The wavelength of the blue light is 450nm; The concentration of the compound shown in Formula I in the organic solvent is 0.1 M-0.4 M; The free radical addition reaction takes 10-16 h.

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