Method for photocatalytic synthesis of azide compound by taking sulfur hexafluoride as oxidizing agent and synthesized azide compound

Abstract

The invention discloses a method for photocatalytic synthesis of azide compounds by taking sulfur hexafluoride as an oxidizing agent, which comprises the following steps: putting a phenyl ethylene compound # imgabs0 # aromatic glycine derivative # imgabs1 # # imgabs2 # azide trimethylsilane, [Ir (ppy) 2 (dtbbpy)] PF6 and a solvent into a reaction container, filling sulfur hexafluoride, and reacting under the illumination condition to synthesize the azide compounds. According to the invention, sulfur hexafluoride is used as an oxidizing agent to synthesize the azide compound, which is reported for the first time internationally and has strong innovativeness; the reaction product is an azide which can be used for click chemical synthesis production; reaction conditions are mild, raw materials are simple and easy to obtain, and potential application value is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of organic photochemistry, and in particular to a method for photocatalytically synthesizing azide compounds using sulfur hexafluoride as an oxidant and the synthesized azide compounds. Background Art

[0002] Sulfur hexafluoride (SF6) is well known for its non-toxicity and high chemical inertness, but SF6 also poses significant challenges due to its resistance to atmospheric degradation. Its greenhouse potential is 22,800 times higher than that of carbon dioxide, its atmospheric lifetime is about 3,200 years, and its continued atmospheric emissions will have a lasting impact on the global environment. Under the same conditions, SF6's insulation capacity is more than 2.5 times that of air and nitrogen, and its arc extinguishing ability is 100 times that of air. It is widely used in power systems. High-purity electronic-grade SF6 is often used as an electronic etchant in the production of integrated circuits such as chips. At present, SF6 is an indispensable insulating protective gas with an industrial-scale production volume of about 10,000 tons / year, and is widely used in the high-voltage power industry (accounting for about 80% of total consumption), plasma etching in semiconductor manufacturing, and metallurgy, and needs to be destroyed after use.

[0003] Typically, activation of this chemically inert gas requires extreme reaction conditions, including high temperature, high pressure, or ultraviolet light irradiation below 190 nanometers, which presents challenges in practical applications. The lack of effective and environmentally friendly degradation methods for large-scale applications and the limitations of its use in chemical transformations have led to an urgency in developing practical applications of SF6 in organic synthesis. Currently, there are only a few mild methods for activating and utilizing SF6.

[0004] The specific methods are:

[0005] Method 1: Activate SF6 using an organic electron donor to produce an effective deoxyfluorination agent (GreenChem. 2017, 19 (11), 2571-2575).

[0006]

[0007] The disadvantage of this method is that the reaction relies on strong base to activate SF6. Strong base is expensive and has high synthesis cost, which is not economically friendly and difficult to use in large-scale reactions. In addition, this method has limited utilization of SF6 and has certain restrictions on the reaction mode.

[0008] Method 2: Irradiation of SF6 with blue light in the presence of tetraethylaminoethylene (TDAE) produces SF5-based reagents. (Angew. Chem. Int. Ed. 2022, 61 (27)).

[0009]

[0010] The disadvantage of this method is that although photocatalysis can be used to activate SF6 during the reaction, it also requires a strong base, has low economic practicality, and is difficult to industrialize.

[0011] In view of the large amount of SF6 to be degraded, it is urgent to explore new models for utilizing this inert gas. Based on the performance of SF6 in chemical transformations, we observed that the key to its participation in the reaction lies in its excellent oxidizing ability. This provides an opportunity to promote organic reactions by using SF6 as a chemical oxidizing agent. However, there are currently no reports on the photocatalytic synthesis of azide compounds using sulfur hexafluoride gas as an oxidant. In order to promote the effective utilization of SF6, it is still necessary to develop an efficient, easy-to-operate, and environmentally friendly photocatalytic synthesis reaction involving SF6 as an oxidant. Summary of the invention

[0012] The technical problem to be solved by the present invention is how to prepare azide compounds using SF6 as an oxidant.

[0013] The present invention solves the above technical problems through the following technical means:

[0014] A method for photocatalytically synthesizing azide compounds using sulfur hexafluoride as an oxidant comprises the following steps: placing phenylethylene compounds, aromatic glycine derivatives, trimethylsilyl azide, a photocatalyst (4,4'-di-tert-butyl-2,2'-bipyridine)bis[(2-pyridyl)phenyl]iridium(III) hexafluorophosphate [Ir(ppy)2(dtbbpy)]PF6 and a solvent in a reaction container, charging sulfur hexafluoride gas as an oxidant, and reacting under light conditions to obtain the azide compounds;

[0015] Wherein, the structural formula of the phenylethylene compound is Wherein R1 and R2 are substituents selected from H, aryl, halogen, C1-C 20 Alkyl, C2-C 20 Alkenyl, C6-C6 with halogen or alkyl or benzene ring substituents 20 One of an aryl group, a 5-10 membered heteroaryl group containing 1-5 heteroatoms or more of O, N, and S, and a conjugated carbonyl group;

[0016] The structural formula of the aromatic glycine derivative is , wherein R3 is a substituent selected from H, halogen, alkoxy, C1-C 20 Alkyl, C2-C 20 Alkenyl, C6-C6 with halogen or alkyl or benzene ring substituents 20Ar is selected from aryl, C6-C6 with halogen or alkyl or benzene ring or alkoxy substituents. 20 One of an aryl group and a 5-10 membered heteroaryl group containing 1-5 one or more heteroatoms selected from O, N and S.

[0017] Description: Under photochemical conditions, sulfur hexafluoride gas as an oxidant reacts with phenylethylene compounds, aromatic glycine derivatives and trimethylsilane TMSN3 (Azidotrimethylsilane) under photocatalysis to generate azide compounds; the reaction formula is as follows:

[0018]

[0019] Preferably, the phenylethylene compound is One of them.

[0020] Preferably, the aromatic glycine derivative is One of them.

[0021] Preferably, the solvent is acetonitrile, DMSO or a mixture of the two.

[0022] Preferably, the solvent is dimethyl sulfoxide (DMSO).

[0023] The present invention is carried out in a single organic solvent system; if necessary, other organic solvents may also be present in the system, but from the perspective of reaction yield and simplicity of operation, it is preferred not to add other organic solvents, that is, to use a single organic solvent as the reaction solvent.

[0024] When the solvent is dimethyl sulfoxide, the yield of the final product is high.

[0025] Preferably, the molar ratio of the phenylethylene compound to the aromatic glycine derivative is 1:1-3.

[0026] Preferably, the molar ratio of the phenylethylene compound to the aromatic glycine derivative is 1:1.5.

[0027] When the molar ratio of the aromatic glycine derivatives to the phenylethylene compounds is 1.5:1, the yield of the final product is high.

[0028] Preferably, the molar ratio of the phenylethylene compound to trimethylsilane is 1:1-5.

[0029] Preferably, the molar ratio of the phenylethylene compound to trimethylsilane is 1:3.

[0030] When the molar ratio of trimethylsilyl azide to the phenylethylene compound is 3:1, the yield of the final product is high.

[0031] Preferably, the molar amount of the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is 0.05-2% of the molar amount of the phenylethylene compound.

[0032] Preferably, the molar amount of the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is 1% of the molar amount of the phenylethylene compound.

[0033] When the molar amount of the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is 1% of the molar amount of the phenylethylene compound, the yield of the final product is high.

[0034] Preferably, the usage ratio of the phenylethylene compound and the solvent is 0.1 mmol:1.0 mL.

[0035] Preferably, the reaction is carried out at room temperature under light conditions.

[0036] Preferably, during the irradiation process, the light source is blue light with a wavelength of 462 nm, and the irradiation time is 10-18 hours.

[0037] Preferably, the irradiation time is 13 hours.

[0038] The present invention also provides an azide compound, which is prepared by the method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant.

[0039] The reaction temperature and reaction time of the present invention can be determined by technicians according to different olefins and aromatic glycine derivatives and actual needs.

[0040] The advantages of the present invention are:

[0041] The reaction temperature of the present invention is room temperature, and cheap and readily available phenylethylene, aromatic glycine derivatives, and trimethylsilyl azide compounds are used as reaction substrates. SF6 gas is used as an oxidant under the condition of no strong base to realize the synthesis of azide compounds, and SF6 is effectively utilized under extremely low cost and simple operation methods. Compared with other methods utilizing SF6 gas, the reaction conditions of the present invention are mild, the reaction raw materials used are cheap and readily available, and SF6 is effectively utilized in the reaction process of synthesizing azide compounds. The present invention has the characteristics of cost saving, simple operation, high utilization rate of SF6, environmental friendliness, novel reaction mode, and easy promotion in industrial production.

[0042] The present invention utilizes sulfur hexafluoride as an oxidant to synthesize azide compounds, which is the first report in the world and is highly innovative. The reaction product is an azide compound, which can be used for click chemistry synthesis production. The reaction conditions are mild, and the raw materials are simple and easily available, which has potential application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is the H NMR spectrum of ethyl 4-azido-3,3-diphenyl-2-(phenylamino)butyrate described in Example 1 of the present invention;

[0044] Figure 2 This is the NMR carbon spectrum of ethyl 4-azido-3,3-diphenyl-2-(phenylamino)butyrate described in Example 1 of the present invention;

[0045] Figure 3 This is the H NMR spectrum of ethyl 4-azido-2-(phenylamino)-3,3-di-p-tolylbutyrate described in Example 2 of the present invention;

[0046] Figure 4 This is the NMR carbon spectrum of ethyl 4-azido-2-(phenylamino)-3,3-di-p-tolylbutyrate described in Example 2 of the present invention;

[0047] Figure 5 This is the H NMR spectrum of ethyl 4-azido-3,3-bis(4-chlorophenyl)-2-(phenylamino)butyrate described in Example 3 of the present invention;

[0048] Figure 6 This is the NMR carbon spectrum of 4-azido-3,3-bis(4-chlorophenyl)-2-(phenylamino)butyric acid ethyl ester described in Example 3 of the present invention;

[0049] Figure 7 This is the H NMR spectrum of ethyl 4-azido-2-((4-methoxyphenyl)amino)-3,3-diphenylbutyrate described in Example 4 of the present invention;

[0050] Figure 8 This is the NMR carbon spectrum of ethyl 4-azido-2-((4-methoxyphenyl)amino)-3,3-diphenylbutyrate described in Example 4 of the present invention;

[0051] Fig. 9 This is the H NMR spectrum of ethyl 4-azido-2-((4-bromophenyl)amino)-3-methyl-3-phenylbutyrate described in Example 5 of the present invention;

[0052] Fig.10 This is the NMR carbon spectrum of ethyl 4-azido-2-((4-bromophenyl)amino)-3-methyl-3-phenylbutyrate described in Example 5 of the present invention;

[0053] Fig.11This is the H NMR spectrum of ethyl 4-azido-3-(4-bromophenyl)-3-methyl-2-(phenylamino)butanoate described in Example 6 of the present invention;

[0054] Fig.12 This is the NMR carbon spectrum of ethyl 4-azido-3-(4-bromophenyl)-3-methyl-2-(phenylamino)butyrate described in Example 6 of the present invention;

[0055] Fig.13 This is the H NMR spectrum of ethyl 4-azido-2-((2-ethoxy-2-oxoethyl)(thiazol-2-yl)amino)-3-methyl-3-phenylbutyrate described in Example 7 of the present invention;

[0056] Fig.14 This is the NMR carbon spectrum of ethyl 4-azido-2-((2-ethoxy-2-oxoethyl)(thiazol-2-yl)amino)-3-methyl-3-phenylbutyrate described in Example 7 of the present invention. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources.

[0059] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0060] In the present invention, "phenylethylene compounds" have the meaning commonly understood by those skilled in the art, namely, styrene and a class of compounds formed by substitution of styrene hydrogen atoms or benzene ring hydrogen atoms, such as 4,4'-(ethylene-1,1-diyl)bis(methylbenzene) and various styrene derivatives.

[0061] In the present invention, "aromatic glycine derivatives" have the meaning commonly understood by those skilled in the art. Phenylglycine is a kind of aromatic amino acid. It is a compound formed by replacing the hydrogen on the α-carbon atom in the carboxylic acid molecule with an amino group or other substituents, so it is also called α-phenylglycine. Its derivatives are a class of compounds formed by replacing the group at the para position of the aromatic ring with an H atom or other substituents, such as ethyl p-tolylglycine and its various derivatives.

[0062] The raw materials used in the following specific examples can all be purchased commercially, and each reagent is purified by means known in the art before use when necessary. 1 H NMR, 13 C NMR was measured using a Bruker Avance 400 spectrometer. The test temperature was room temperature, the solvent was deuterated chloroform, and the reference was selected: 1 H NMR: CHCl3 7.260 ppm; 13 CNMR: CHCl3 is 77.000ppm.

[0063] Example 1

[0064] Synthesis of 4-azido-3,3-diphenyl-2-(phenylamino)butyric acid ethyl ester

[0065] In an 8mL sample bottle equipped with a magnetic stirrer, 1,1-diphenylethylene (36.0 mg, 0.2 mmol), ethyl phenylglycine (53.7 mg, 0.3 mmol), trimethylsilane (69.1 mg, 0.6 mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0 mg, 0.002 mmol), dimethyl sulfoxide DMSO (2.0 mL) were dissolved to form a solution of 1,1-diphenylethylene, ethyl phenylglycine, trimethylsilane and photocatalyst, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a LED blue light with a wavelength of 462 nm for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 60.8 mg of ethyl 4-azido-3,3-diphenyl-2-(phenylamino)butyrate, with a yield of 76%.

[0066] The NMR spectrum of the product 4-azido-3,3-diphenyl-2-(phenylamino)butyric acid ethyl ester is as follows Figure 1-2 As shown, the NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.42-7.28(m,10H),7.24-7.20(m,2H),6.84(t,J=7.3Hz,1H),6.77(d,J=8.0Hz,2H),5.11( s,1H),4.58(s,1H),4.52(d,J=12.0Hz,1H),4.30(d,J=12.0Hz,1H),4.01-3.86(m,2H),1.01(t,J=7.1Hz,3H)ppm.

[0067] 13C NMR (101MHz, CDCl3) δ171.9,146.3,142.0,141.1,129.3,128.9,128.8,128.2,128.0,127.5,127.2,118.7,113.8,61.0,60.8,58.1,53.8,13.7ppm.

[0068] HRMS(ESI)m / z calculation for[C 24 H 25 N4O2,M+H] + :401.1972;Found:401.1966.

[0069]

[0070] According to the synthesis method in Example 1, the reaction conditions were changed as shown in the following table, and the remaining steps were the same as in Example 1. The yields are shown in the following table:

[0071]

[0072] Standard reaction conditions: 1 0.2mmol, photocatalyst 10mmol%, solvent 2.0mL, time 13h, room temperature. a O2(balloon). b 0.2mmol (1.0equiv.) di-tert-butyl peroxide. c 0.2mmol (1.0equiv.) Na2S2O8. The yield is the isolated yield. DMSO dimethyl sulfoxide; MeCN acetonitrile.

[0073] Example 2

[0074] Synthesis of Ethyl 4-Azido-2-(Phenylamino)-3,3-Di-p-Tolylbutyrate

[0075] In an 8 mL sample bottle equipped with a magnetic stirrer, 4,4'-(ethylene-1,1-diyl)bis(methylbenzene) (41.6 mg, 0.2 mmol), ethyl phenylglycine (53.7 mg, 0.3 mmol), trimethylsilane (69.1 mg, 0.6 mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0 mg), and dimethyl sulfoxide DMSO (2.0 mL) were added to dissolve to form a solution of 4,4'-(ethylene-1,1-diyl)bis(methylbenzene), ethyl phenylglycine, trimethylsilane and photocatalyst, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a 462 nm LED blue light for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 60.0 mg of ethyl 4-azido-2-(phenylamino)-3,3-di-p-tolylbutyrate with a yield of 70%.

[0076] The NMR spectrum of the product 4-azido-2-(phenylamino)-3,3-di-p-tolylbutyric acid ethyl ester is as follows Figure 3-4 As shown, the NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.27-7.09(m,10H),6.82(t,J=7.4Hz,1H),6.75(d,J=7.5Hz,2H),5.08(d,J=10.3Hz,1H),4.52(d,J=10.4 Hz,1H),4.45(d,J=12.0Hz,1H),4.26(d,J=12.0Hz,1H),4.03-3.91(m,2H),2.41(s,3H),2.39(s,3H),1.03(t,J=7.1Hz,3H)ppm.

[0077] 13 C NMR (101MHz, CDCl3) δ172.0,146.3,139.0,138.0,137.1,136.8,129.2,128.8,1 28.7,128.6,128.6,118.6,113.7,60.9,60.6,58.3,53.2,20.9,20.9,13.7ppm.

[0078] HRMS(ESI)m / z calculation for[C 26 H 29 N4O2,M+H] + :429.2285;Found:429.2284.

[0079] Example 3

[0080] Synthesis of 4-azido-3,3-bis(4-chlorophenyl)-2-(phenylamino)butyric acid ethyl ester

[0081] In an 8 mL sample bottle equipped with a magnetic stirrer, 4,4'-(ethylene-1,1-diyl)bis(chlorobenzene) (49.6 mg, 0.2 mmol), ethyl phenylglycine (53.7 mg, 0.3 mmol), trimethylsilane (69.1 mg, 0.6 mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0 mg), and dimethyl sulfoxide DMSO (2.0 mL) were added to dissolve to form a solution of 4,4'-(ethylene-1,1-diyl)bis(chlorobenzene), ethyl phenylglycine, trimethylsilane and photocatalyst, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a LED blue light with a wavelength of 462 nm for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 63.7 mg of ethyl 4-azido-3,3-bis(4-chlorophenyl)-2-(phenylamino)butyrate with a yield of 68%.

[0082] The NMR spectrum of the product 4-azido-3,3-bis(4-chlorophenyl)-2-(phenylamino)butyric acid ethyl ester is as follows Figure 5-6 As shown, the NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.37-7.29(m,4H),7.24-7.21(m,3H),7.11-7.08(m,3H),6.83(t,J=7.3Hz,1H),6.73(d,J=8.4Hz,2H),5.01(d,J= 10.9,2.2Hz,1H),4.40(d,J=12.0Hz,1H),4.32(d,J=10.8Hz,1H),4.16(d,J=12.0Hz,1H),4.00-3.88(m,2H),1.01(t,J=7.2Hz,3H)ppm.

[0083] 13 C NMR (101MHz, CDCl3) δ171.5,145.9,139.9,139.2,133.7,133.5,130.3,130.2,129.4,128.4,128.2,119.3,114.1,61.3,60.6,57.9,53.5,13.8ppm.

[0084] HRMS(ESI)m / z calculation for[C 24 H 23 Cl2N4O2,M+H] +:469.1193;Found:469.1186.

[0085] Example 4

[0086] Synthesis of ethyl 4-azido-2-((4-methoxyphenyl)amino)-3,3-diphenylbutyrate

[0087] In an 8mL sample bottle equipped with a magnetic stirrer, 1,1-diphenylethylene (36.0 mg, 0.2 mmol), 4-methoxyphenylglycine ethyl ester (62.7 mg, 0.3 mmol), trimethylsilane (69.1 mg, 0.6 mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0 mg), dimethyl sulfoxide DMSO (2.0 mL) were dissolved to form a solution of 1,1-diphenylethylene, 4-methoxyphenylglycine ethyl ester, trimethylsilane and photocatalyst, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a LED blue light with a wavelength of 462 nm for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 35.3 mg of 4-azido-2-((4-methoxyphenyl)amino)-3,3-diphenylbutyric acid ethyl ester, with a yield of 41%.

[0088] The NMR spectrum of the product 4-azido-2-((4-methoxyphenyl)amino)-3,3-diphenylbutyric acid ethyl ester is as follows Figure 7-8 As shown, the NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.35-7.29(m,8H),7.18-7.16(m,2H),6.80-6.78(m,2H),6.69-6.67(m,2H),4.97(s,1H),4.43(d ,J=12.0Hz,1H),4.21(d,J=12.0Hz,1H),3.93-3.84(m,2H),3.78-3.77(m,1H),3.75(s,3H),0.96(t,J=7.1Hz,3H)ppm.

[0089] 13 C NMR (101MHz, CDCl3) δ172.1,153.0,142.0,141.2,140.4,129.0,129.0,128. 1,127.9,127.5,127.2,115.6,114.8,61.9,60.9,58.4,55.6,54.1,13.8ppm.

[0090] HRMS(ESI)m / z calculation for[C 25 H27 N4O3,M+H] + :431.2078;Found:431.2075.

[0091] Example 5

[0092] Synthesis of 4-azido-2-((4-bromophenyl)amino)-3-methyl-3-phenylbutyric acid ethyl ester

[0093] In an 8mL sample bottle equipped with a magnetic stirrer, methylphenylethylene (23.6mg, 0.2mmol), 4-bromophenylglycine ethyl ester (77.1mg, 0.3mmol), trimethylsilane (69.1mg, 0.6mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0mg), dimethyl sulfoxide DMSO (2.0mL) were dissolved to form a solution of methylphenylethylene, 4-bromophenylglycine ethyl ester, trimethylsilane and photocatalyst, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a LED blue light with a wavelength of 462nm for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 45.9mg of 4-azido-2-((4-bromophenyl)amino)-3-methyl-3-phenylbutyric acid ethyl ester, with a yield of 55%.

[0094] The NMR spectrum of the product 4-azido-2-((4-bromophenyl)amino)-3-methyl-3-phenylbutyric acid ethyl ester is as follows Figure 9-10 As shown, the NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.41-7.31(m,10H),7.28-7.23(m,4H),6.58-6.56(m,2H),6.5 1-6.49(m,2H),4.33(d,J=10.5Hz,1H),4.27(d,J=10.4Hz,1H),4.22(d,J=10.6Hz,1 H),4.08(q,J=7.1Hz,2H),4.00-3.88(m,5H),3.80(d,J=12.2Hz,1H),3.75(d,J=12. 0Hz,1H),1.61(s,3H),1.57(s,3H),1.15(t,J=7.1Hz,3H),0.94(t,J=7.1Hz,3H)ppm.

[0095] 13C NMR (101MHz, CDCl3) δ171.6,171.5,146.1,145.9,140.5,140.1,132.0,131.9,128.5,128.4,127.5,127.4,126. 8,126.7,115.8,115.8,110.7,110.7,63.2,63.0,61.2,61.0,59.0,58.7,45.9,45.5,20.5,19.4,14.0,13.7ppm.

[0096] HRMS(ESI)m / z calculation for[C 19 H 22 BrN4O2,M+H] + :417.0921;Found:417.0915.

[0097] Example 6

[0098] Synthesis of 4-azido-3-(4-bromophenyl)-3-methyl-2-(phenylamino)butyric acid ethyl ester

[0099] 1-Bromo-4-(prop-1-en-2-yl)benzene (39.2 mg, 0.2 mmol), ethyl phenylglycine (53.7 mg, 0.3 mmol), trimethylsilane (69.1 mg, 0.6 mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0 mg), dimethyl sulfoxide DMSO (2.0 mL) were added to an 8 mL sample bottle equipped with a magnetic stirrer to dissolve 1-Bromo-4-(prop-1-en-2-yl)benzene, ethyl phenylglycine, trimethylsilane and photocatalyst solution, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a LED blue light with a wavelength of 462 nm for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 44.9 mg of ethyl 4-azido-3-(4-bromophenyl)-3-methyl-2-(phenylamino)butyrate with a yield of 54%.

[0100] The NMR spectrum of the product 4-azido-3-(4-bromophenyl)-3-methyl-2-(phenylamino)butyric acid ethyl ester is as follows Figure 11-12 As shown, the NMR data are as follows: 1H NMR (400MHz, CDCl3) δ7.54–7.52(m,4H),7.34–7.32(m,2H),7.26–7.18(m,6H),6. 82(q,J=7.7Hz,2H),6.73(d,J=8.0Hz,2H),6.67(d,J=7.8Hz,2H),4.39–4.33(m,2 H),4.23–4.20(m,1H),4.10(q,J=7.1Hz,2H),3.94–3.91(m,5H),3.79(d,J=12.4H z,2H),1.61(s,3H),1.58(s,3H),1.19(t,J=7.1Hz,3H),0.97(t,J=7.1Hz,3H)ppm.

[0101] 13 C NMR (101MHz, CDCl3) δ171.6,171.6,146.8,146.7,140.0,139.4,131.4,131.3,129.3,129.3,128.8,128.7,121. 5,121.4,119.2,119.2,114.4,114.3,63.0,62.9,61.2,61.0,58.9,58.5,45.8,45.4,20.4,19.0,14.0,13.7ppm.

[0102] HRMS (ESI) m / z [M+H] + Calcd for C 19 H 22 BrN4O2 + 417.0921; Found:417.0913.

[0103] Example 7

[0104] Synthesis of ethyl 4-azido-2-((2-ethoxy-2-oxoethyl)(thiazol-2-yl)amino)-3-methyl-3-phenylbutyrate

[0105] In an 8 mL sample bottle equipped with a magnetic stirrer, prop-1-en-2-ylbenzene (23.6 mg, 0.2 mmol), diethyl 2,2'-(thiazol-2-yl nitrogen diyl) diacetate (81.6 mg, 0.3 mmol), trimethylsilane (69.1 mg, 0.6 mmol), photocatalyst [Ir(ppy)2(dtbbpy)]PF6 (2.0 mg), dimethyl sulfoxide DMSO (2.0 mL) were dissolved to form a solution of prop-1-en-2-ylbenzene, diethyl 2,2'-(thiazol-2-yl nitrogen diyl) diacetate, trimethylsilane and photocatalyst, and the sample bottle cap was covered. The solution was bubbled with a balloon filled with SF6 gas for 5 minutes, and then irradiated with a LED blue light with a wavelength of 462 nm for 13 hours under stirring at room temperature. After the reaction was completed, the solvent was removed in vacuo and column chromatography was performed to obtain 35.4 mg of ethyl 4-azido-2-((2-ethoxy-2-oxoethyl)(thiazol-2-yl)amino)-3-methyl-3-phenylbutyrate with a yield of 41%.

[0106] The NMR spectrum of the product 4-azido-2-((2-ethoxy-2-oxoethyl)(thiazol-2-yl)amino)-3-methyl-3-phenylbutyric acid ethyl ester is as follows Figure 13-14 As shown, the NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.45–7.41(m,4H),7.34–7.27(m,4H),7.25–7.21(m,2H),6.53(d,J=4. 9Hz,2H),5.92(dd,J=4.9,1.0Hz,2H),4.70–4.61(m,2H),4.31–4.18(m,6H),3.99(d,J=12.4 Hz,1H),3.91–3.78(m,7H),3.69(s,1H),3.51(d,J=12.1 Hz,1H),1.61(s,3H),1.54(s,3H),1.33–1.28(m,6H),0.96–0.89(m,6H)ppm.

[0107] 13 C NMR(101 MHz, CDCl3)δ170.8,170.5,168.4,168.3,160.1,156.0,142.3,141.9,128.0,127.9,127.2,127.1,127.1,127.0,126.7,1 26.7,97.8,97.7,74.9,73.3,61.6,60.3,60.2,59.6,58.0,47.5,47.5,46.7,46.6,21.7,18.2,14.2,14.2,13.8,13.7ppm.

[0108] HRMS (ESI) m / z [M+H] + Calcd for C 20 H 26 N5O4S + 432.1700; Found:432.1694.

[0109]

[0110]

[0111] As can be seen from Examples 1-7, the method of the present invention is to synthesize azide compounds from cheap and readily available trimethylsilyl azide, phenylethylene, and aromatic glycine derivative compounds, using sulfur hexafluoride gas as an oxidant under photochemical conditions (when sulfur hexafluoride is not used, the reaction does not occur, and when other oxidants are used instead of sulfur hexafluoride, the reaction can occur, so the role of sulfur hexafluoride is consistent with that of other oxidants).

[0112] Comparative Example 1

[0113] Control experiment (compared with Example 1): The conditions in Example 1 were changed, and the yields were shown in the following table:

[0114]

[0115] In the table, / means not used, √ means used. According to the control experiment, the target product cannot be obtained without SF6; the target product cannot be obtained without adding photocatalyst; and the target product cannot be obtained without LED blue light.

[0116] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for photocatalytically synthesizing azide compounds using sulfur hexafluoride as an oxidant, characterized in that: The following steps are involved: A phenylethylene compound, an aromatic glycine derivative, trimethylsilyl azide, a photocatalyst [Ir(ppy)2(dtbbpy)]PF6 and a solvent are placed in a reaction container, sulfur hexafluoride gas is introduced as an oxidant, and the reaction is carried out under light conditions to obtain the azide compound; Wherein, the structural formula of the phenylethylene compound is Wherein R1 and R2 are substituents selected from H, aryl, halogen, C1-C 20 Alkyl, C2-C 20 Alkenyl, C6-C6 with halogen or alkyl or benzene ring substituents 20 One of an aryl group, a 5-10 membered heteroaryl group containing 1-5 heteroatoms or more of O, N, and S, and a conjugated carbonyl group; The structural formula of the aromatic glycine derivative is Wherein R3 is a substituent selected from H, halogen, alkoxy, C1-C 20 Alkyl, C2-C 20 Alkenyl, C6-C6 with halogen or alkyl or benzene ring substituents 20 Ar is selected from aryl, C6-C6 with halogen or alkyl or benzene ring or alkoxy substituents. 20 One of an aryl group and a 5-10 membered heteroaryl group containing 1-5 one or more heteroatoms selected from O, N and S.

2. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The phenylethylene compound is One of them.

3. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The aromatic glycine derivatives are One of them.

4. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The solvent is acetonitrile, DMSO or a mixture of the two.

5. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The molar ratio of the phenylethylene compound to the aromatic glycine derivative is 1:1-3.

6. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The molar ratio of the phenylethylene compound to trimethylsilane is 1:1-5.

7. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The molar amount of the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is 0.05-2% of the molar amount of the phenylethylene compound.

8. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to claim 1, characterized in that: The usage ratio of the phenylethylene compound and the solvent is 0.1 mmol:1.0 mL.

9. The method for photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant according to any one of claims 1 to 8, characterized in that: During the illumination process, the light source is blue light with a wavelength of 462nm, and the illumination time is 10-18 hours.

10. An azide compound, characterized in that: The method is prepared by using the photocatalytic synthesis of azide compounds using sulfur hexafluoride as an oxidant as described in any one of claims 1 to 9.

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