Synthetic method for photocatalytic synthesis of sigma-amino silicon

Abstract

The invention belongs to the technical field of organic chemical synthesis, and discloses a synthetic method for photocatalytic synthesis of sigma-amino silicon. According to the invention, silicon-based carboxylic acid with a wide source is used as a raw material and is converted into stable silicon-based oxime ester through one step for the first time, and the stable silicon-based oxime ester reacts with olefin under the excitation of visible light to generate a series of amino silicon derivatives. The method has the advantages of mild reaction conditions, convenience in experimental operation, good substrate compatibility, easiness in scale amplification and the like, and meets the industrial production requirements. Research finds that the highest yield of the product can reach 80%, and the generated compound has wide application prospects in organic synthesis and drug research and development. Therefore, the method has great application value and social and economic benefits.

Description

Technical Field

[0001] This invention belongs to the field of organic chemical synthesis technology, and relates to a photocatalytic synthesis method for σ-aminosilicon. Background Technology

[0002] Organosilicon compounds have found wide applications in organic synthesis, materials science, and the development of new drugs and agrochemicals. Due to its unique physicochemical properties and its position in the periodic table, silicon has been studied as a source of various bioactive molecules. 3 Carbon isosteric substitutes. Due to their relevance to medicinal chemistry, silicon- and amino-containing building blocks constitute an important subclass of organosilicon compounds. In particular, aminosilanes are found in many analogues of currently approved drugs, such as: Silperisone, a muscle relaxant; R-Sila-venlafaxine, a drug for treating depression; Karenitecin BNP1350, an antitumor drug; Silafluofen, an insecticide; and Sila-haloperidol, a psychotropic drug, etc. Therefore, developing a method to obtain this structure has become an important goal in the development of synthetic methods.

[0003] Over the past few decades, numerous synthetic methods for aminosilyl compounds have been reported [see: (a) Y. Yang, R. Song, S. Luo, Iron-Catalyzed Intermolecular 1,2-Difunctionalization of Styrenes and Conjugated Alkenes with Silanes and Nucleophiles[J], Angew. Chem. Int. Ed. 2017, 56, 7916-7919. (b) Z. Liu, J. Chen, KM Engle, et al, Palladium(0)-Catalyzed Directed syn-1,2-Carboboration and Silylation: Alkene Scope, Applications in DEA romatization, and Stereocontrol by a Chiral Auxiliary[J], Angew. Chem. Int. Ed. 2019, 58, 17068-17073. (c) Y. Zeng, X. Liu, X. Guo, et al. al,Cu / chiral phosphoric acid-catalyzedradical-initiated asymmetric aminosilylation of alkene with hydrosilane[J].Sci. China Chem.2019, 62, 1529-1536. (d) W. Cui, W. Zhao, Z. Yao, et al,Diastereoselective Synthesis of Polysubstituted Piperidines through Visible-Light-Driven Silylative Cyclization of Aza-1,6-Dienes: Experimental and DFTStudies[J], Chem. Eur. J.2019, 25, 16506-16510. (e) T. Kobayashi, S. Nishino,K. Hirano, et al, Synthesis of β -Silyl- α-amino Acid Derivatives by Cu-Catalyzed Regio and Enantioselective Silylamination of α,β -Unsaturated Esters[J], Org. Lett.2022, 24, 1418-1422. (f) Y. Shao, C. Ying, J. Hou, et al,Synthesis of β -Silyl Amines via Merging Photoinduced Energy and Hydrogen Atom Transfer in Flow[J], Org. Lett.2024, 26, 8486-8491.]. These reactions can be summarized as nucleophilic / electophilic addition, transition metal catalysis, and photocatalysis. However, these reactions still have some drawbacks, such as harsh reaction conditions, complex operation, limited substrate range, and expensive catalysts. Therefore, a simple reaction system was developed, starting from inexpensive and readily available raw materials, to synthesize Silyl Amines using visible light-driven synthesis. σ -Aminosilicon has significant research value and application potential.

[0004] As is well known, silyl carboxylic acids are a class of widely available raw material chemicals with relatively stable properties. They can be converted in one step to the corresponding silyl oxime esters via a reaction with oximes. Under visible light-induced radical cleavage of the nitrogen-oxygen bond, silyl radicals and alkyl radicals can be generated, which can then undergo a series of subsequent reactions.

[0005] This invention uses stable and widely available silyl carboxylic acids as raw materials, which are converted into stable silyl oxime esters in one step. Under visible light excitation, these esters react with alkenes to generate a series of aminosilicon derivatives. Compared to traditional synthetic methods, visible light, as a green energy source, offers milder reaction conditions and better functional group compatibility, thus providing a new approach for the green and efficient synthesis of aminosilicon compounds. Summary of the Invention

[0006] This invention provides a novel synthetic method for preparing aminosilicon compounds by promoting the reaction of silyl oxime esters with olefins under photoexcitation. This method has advantages such as mild reaction conditions, convenient experimental operation, good substrate compatibility, and easy scale-up, thus possessing significant application value and socio-economic benefits.

[0007] The technical solution of this invention: A photocatalytic synthesis method for σ-aminosilicon involves preparing a series of aminosilicon compounds from olefins and silyl oxime esters under light irradiation. The synthetic route is as follows: The steps are as follows: Photocatalyst, olefin, silyl oxime ester, and solvent were added sequentially to the reaction flask, and the reaction flask was irradiated under blue light. R of olefins 1 It is an aromatic ring or a cyano group, wherein the aromatic ring is a phenyl group whose para position is further replaced by a halogen, trifluoromethyl, phenyl, carboxyl, methoxy, formyl or other substituents, or the aromatic ring is a naphthalene ring or a pyridine ring. R of silyl oxime esters 2 R 3 R 4 It is methyl Solvents include toluene, n-hexane, tetrahydrofuran, and 1,4-dioxane. N,N -Dimethylformamide, N,N - One or more of dimethylacetamide, ethyl acetate, dichloromethane, acetone, and acetonitrile, preferably ethyl acetate and dichloromethane.

[0008] The photocatalyst is thioxanth-9-one, thioxanth-9-one derivatives, 2,4,5,6-tetra(9-carbazolyl)-isophthalonitrile, tris-(2-phenylpyridine)iridium, etc., with thioxanth-9-one being preferred.

[0009] The concentration of olefins in the system is 0.1 M-0.3 M.

[0010] The molar ratio of olefin to silyl oxime ester is 1:1.0 to 1:2.0.

[0011] The molar ratio of olefin to photocatalyst is 1:0.01 to 1:0.1.

[0012] The reaction time ranges from 2 to 18 hours, preferably from 4 to 12 hours.

[0013] The intensity of blue light is 10 W-40 W.

[0014] Blue light has a wavelength of 390 nm-456 nm.

[0015] The beneficial effects of this invention are as follows: This invention provides a photocatalytic synthesis method for σ-aminosilicon, achieving for the first time a method for synthesizing aminosilicon from olefins and silyl oxime esters under photocatalytic conditions, filling a gap in existing technologies. The method of this invention features mild process conditions, a short process flow, simple steps, and wide substrate applicability, meeting the requirements of industrial production. Studies have shown that the product yield can reach up to 80%, and the generated aminosilicon compounds have broad application prospects in organic synthesis and drug development. Therefore, this invention has significant application value. Attached Figure Description

[0016] Figure 1 For compound 3a 1 H-NMR spectrum.

[0017] Figure 2 For compound 3a 13 C-NMR spectrum.

[0018] Figure 3 For compound 3b 1 H-NMR spectrum.

[0019] Figure 4 For compound 3b 13 C-NMR spectrum.

[0020] Figure 5 For compound 3c 1 H-NMR spectrum.

[0021] Figure 6 For compound 3c 13 C-NMR spectrum.

[0022] Figure 7 For compound 3d 1 H-NMR spectrum.

[0023] Figure 8 For compound 3d 13 C-NMR spectrum.

[0024] Figure 9 For compound 3e 1 H-NMR spectrum.

[0025] Figure 10 For compound 3e 13 C-NMR spectrum.

[0026] Figure 11 For compound 3f 1 H-NMR spectrum.

[0027] Figure 12 For compound 3f 13 C-NMR spectrum.

[0028] Figure 13 3g of compound 1 H-NMR spectrum.

[0029] Figure 14 3g of compound 13 C-NMR spectrum.

[0030] Figure 15 For compound 3h 1 H-NMR spectrum.

[0031] Figure 16For compound 3h 13 C-NMR spectrum.

[0032] Figure 17 For compound 3i 1 H-NMR spectrum.

[0033] Figure 18 For compound 3i 13 C-NMR spectrum.

[0034] Figure 19 For compound 3j 1 H-NMR spectrum.

[0035] Figure 20 For compound 3j 13 C-NMR spectrum. Detailed Implementation

[0036] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

[0037] Example 1: Synthesis of 2-amino-5-(trimethylsilyl)pentanenitrile [3a]; Acrylonitrile (13.3 μL, 0.2 mmol), benzophenone O-(3-(trimethylsilyl)propionyl)oxime (97.6 mg, 0.3 mmol), and thioxanthone (0.2 mg, 0.0001 mmol) were accurately weighed into an 8 mL reaction flask in a glove box, followed by ethyl acetate (2.0 mL). The resulting mixture was stirred for 4 hours at room temperature under blue LED (390 nm, 40 W) irradiation. After the reaction was complete, the reaction mixture was diluted with ethyl acetate, filtered, and concentrated under reduced pressure. 3 mL of tetrahydrofuran and 3 mL of 1 M hydrochloric acid solution were added, and the mixture was stirred at room temperature for 3 h. The residue was extracted, alkalized, dried, and concentrated under reduced pressure. The residue was purified by rapid chromatography. The yield of 2-amino-5-(trimethylsilyl)pentanonitrile was 80%. 1 H NMR (500 MHz, CDCl3) δ 3.69 (t, J =7.2 Hz, 1H), 1.81–1.74 (m, 2H), 1.72 (s, 2H), 1.56–1.44 (m, 2H), 0.62 – 0.45(m, 2H), 0.00 (s, 9H); 13 C NMR (126 MHz, CDCl3) δ122.35, 43.20, 39.10, 20.19, 16.30, -1.61. Example 2: Synthesis of N-(1-(4-fluorophenyl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine [N-(1-(4-fluorophenyl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine] (3b); Accurately weigh 35.8 μL (0.3 mmol) of 4-fluorostyrene, 146.5 mg (0.45 mmol) of benzophenone O-(3-(trimethylsilyl)propionyl)oxime (0.3 mg, 0.00015 mmol), and thioxanth-9-one (0.3 mg, 0.00015 mmol) into an 8 mL reaction flask, followed by 3.0 mL of dichloromethane. Stir the resulting mixture at room temperature under blue LED (390 nm, 40 W) illumination for 8 hours. After the reaction was complete, dilute the reaction mixture with ethyl acetate, filter, and concentrate under reduced pressure. Purify the residue by rapid chromatography. The yield of N-(1-(4-fluorophenyl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethyleneimine was 60%. 1 HNMR (400 MHz, CDCl3) δ 7.60 (d, J =6.6 Hz, 2H), 7.39–7.33 (m, 3H), 7.31–7.23 (m,3H), 7.20 (dd, J =8.5, 5.7 Hz, 2H), 7.01–6.95 (m, 2H), 6.90 (t, J =8.8 Hz, 2H), 4.28 (dd, J =8.1, 5.3 Hz, 1H), 1.94–1.82 (m, 1H), 1.75–1.64 (m, 1H), 1.24–1.15(m, 1H), 1.11–0.98 (m, 1H), 0.36–0.27 (m, 2H), -0.14 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 166.70, 161.70(d, J = 244.4Hz), 141.28, 141.25, 140.12, 137.27, 130.02,128.67, 128.55(d, J= 8.1Hz), 128.45, 128.15, 127.96, 115.12(d, J = 21.2Hz),77.48, 77.16, 76.84, 65.85, 43.65, 20.98, 16.54, -1.47. Example 3: Synthesis of 1,1-diphenyl-N-(1-(4-(trifluoromethyl)phenyl)-4-(trimethylsilyl)butyl)methanimine [1,1-diphenyl-N-(1-(4-(trifluoromethyl)phenyl)-4-(trimethylsilyl)butyl)methanimine] (3c); Accurately weigh 44.4 μL (0.3 mmol), benzophenone O-(3-(trimethylsilyl)propionyl)oxime (146.5 mg, 0.45 mmol), and 2,4,5,6-tetrakis(9-carbazolyl)-isophthalonitrile (1.2 mg, 0.00015 mmol) into an 8 mL reaction flask, followed by 3.0 mL of ethyl acetate. The resulting mixture was stirred for 8 hours at room temperature under blue LEDS (456 nm, 40 W). After the reaction was complete, the reaction mixture was diluted with ethyl acetate, filtered, and concentrated under reduced pressure. The residue was purified by rapid chromatography. The yield of 1,1-diphenyl-N-(1-(4-(trifluoromethyl)phenyl)-4-(trimethylsilyl)butyl)imine was 62%. 1 H NMR (400 MHz, CDCl3) δ 7.70 (dt, J =6.8, 1.6 Hz, 2H), 7.57 (d, J =8.1 Hz, 2H), 7.45 (dd, J =6.8, 2.8 Hz, 5H), 7.41–7.33 (m, 3H), 7.09–7.00 (m, 2H), 4.44 (dd, J =8.2, 5.0 Hz, 1H), 2.07–1.93 (m, 1H), 1.87–1.74(m, 1H), 1.35–1.27 (m, 1H), 1.21–1.10 (m, 1H), 0.46–0.36 (m, 2H), -0.05 (s,9H). 13 C NMR (101 MHz, CDCl3) δ167.35, 149.65, 139.93, 137.08, 132.58, 130.23,130.18, 129.30, 128.98, 128.69, 128.58, 128.53, 128.42, 128.03(q, J = 35.1 Hz), 125.35(q, J = 3.8 Hz), 124.48(q, J = 272.7 Hz),, 77.48, 77.16, 76.84, 66.19, 43.59, 21.01, 16.50, -1.49. Example 4: Synthesis of N-(1-([1,1'-biphenyl]-4-yl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine [N-(1-([1,1'-biphenyl]-4-yl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine](3d); Accurately weigh 54.1 mg (0.3 mmol) of 4-phenylstyrene, 146.5 mg (0.45 mmol) of benzophenone O-(3-(trimethylsilyl)propionyl)oxime, and 0.3 mg (0.00015 mmol) of thioxanthone-9-one into an 8 mL reaction flask, followed by 3.0 mL of dichloromethane. Stir the resulting mixture at room temperature under blue LEDS (390 nm, 40 W) irradiation for 8 hours. After the reaction was complete, dilute the reaction mixture with ethyl acetate, filter, and concentrate under reduced pressure. The residue was purified by rapid chromatography. The yield of N-(1-([1,1'-biphenyl]-4-yl)-4-(trimethylsilyl)butyl)-1,1-diphenylimine was 67%. 1 H NMR (400 MHz, CDCl3) δ 7.76 (dd, J =8.1, 1.7 Hz, 2H), 7.67–7.63 (m,2H), 7.62–7.57 (m, 2H), 7.47 (dq, J =11.7, 3.6 Hz, 7H), 7.43–7.34 (m, 4H), 7.19–7.11 (m, 2H), 4.48 (dd, J=8.3, 5.1 Hz, 1H), 2.09 (m, 1H), 1.95–1.85 (m,1H), 1.45–1.35 (m, 1H), 1.29–1.17 (m, 1H), 0.53–0.44 (m, 2H), 0.00 (s, 9H). 13 CNMR (101 MHz, CDCl3) δ 166.67, 144.71, 141.28, 140.23, 139.49, 138.19, 137.33, 132.53, 130.19, 129.96, 128.82, 128.72, 128.42, 128.13, 128.07, 127.61, 127.15, 66.30, 43.58, 21.12, 16.56, -1.43. Example 5: Synthesis of N-(1-(4-chlorophenyl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine [N-(1-(4-chlorophenyl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine] (3e); Accurately weigh 36 μL (0.3 mmol) of 4-chlorostyrene, 146.5 mg (0.45 mmol) of benzophenone O-(3-(trimethylsilyl)propionyl)oxime (0.3 mg, 0.00015 mmol) in a glove box and add them to an 8 mL reaction flask, followed by 3.0 mL of acetonitrile. The resulting mixture was stirred for 8 hours at room temperature under blue LEDS (390 nm, 40 W). After the reaction was complete, the reaction mixture was diluted with ethyl acetate, filtered, and concentrated under reduced pressure. The residue was purified by rapid chromatography. The yield of N-(1-(4-chlorophenyl)-4-(trimethylsilyl)butyl)-1,1-diphenylimine was 61%. 1 H NMR (400 MHz, CDCl3) δ 7.70 (d, J =6.6 Hz, 2H), 7.50–7.43 (m, 3H), 7.38 (dd, J =11.1, 7.2 Hz, 3H), 7.28 (d, J =1.2 Hz, 4H), 7.08 (dt, J =6.9, 3.3 Hz, 2H), 4.37 (dd,J =8.1, 5.2, 1H), 2.06–1.92 (m, 1H), 1.86–1.73 (m, 1H), 1.32–1.28 (m, 1H), 1.24–1.08 (m, 1H), 0.42 (t, J =8.4 Hz, 2H), -0.04 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 166.96, 144.10, 140.04, 137.19, 132.17, 130.06, 128.67, 128.54, 128.51, 128.46, 128.16, 127.92, 65.89, 43.57, 20.97, 16.53, -1.47. Example 6: Synthesis of 4-(1-((diphenylmethylene)amino)-4-(trimethylsilyl)butyl)benzoic acid [3f]; Accurately weigh 4-vinylbenzoic acid (44.6 mg, 0.3 mmol), benzophenone O-(3-(trimethylsilyl)propionyl)oxime (146.5 mg, 0.45 mmol), and 2,4,5,6-tetrakis(9-carbazolyl)-isophthalonitrile (1.2 mg, 0.00015 mmol) into an 8 mL reaction flask, followed by 3.0 mL of dichloromethane. Stir the resulting mixture at room temperature for 10 hours under blue LEDS (456 nm, 40 W). After the reaction was complete, dilute the reaction mixture with ethyl acetate, filter, and concentrate under reduced pressure. Purify the residue by rapid chromatography. The yield of 4-(1-((diphenylmethylene)amino)-4-(trimethylsilyl)butyl)benzoic acid was 62%. 1 H NMR (400 MHz, CDCl3) δ 11.20 (s, 1H), 8.07 (d, J =8.0Hz, 2H), 7.76–7.66 (m, 2H), 7.47–7.33 (m, 8H), 7.10–7.00 (m, 2H), 4.46 (dd, J=8.2, 5.0 Hz, 1H), 2.07–1.97 (m, 1H), 1.88–1.75 (m, 1H), 1.38–1.24 (m, 2H), 1.24–1.09 (m, 1H), 0.41 (t, J =8.4 Hz, 2H), -0.05 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 172.33, 167.62, 151.82, 139.94, 137.10, 130.46, 130.22, 130.17, 128.73, 128.58, 128.51, 128.19, 127.88, 127.29, 66.42, 43.44, 21.01, 16.51, -1.48. Example 7: Synthesis of 4-(1-((diphenylmethylene)amino)-4-(trimethylsilyl)butyl)phenyl acetate [3g]; Accurately weigh 4-vinylphenylacetate (46 μL, 0.3 mmol), benzophenone O-(3-(trimethylsilyl)propionyl)oxime (146.5 mg, 0.45 mmol), and thioxanth-9-one (0.3 mg, 0.00015 mmol) into an 8 mL reaction flask, followed by ethyl acetate (3.0 mL). Stir the resulting mixture at room temperature under blue LEDS (390 nm, 10 W) irradiation for 12 hours. After the reaction was complete, dilute the reaction mixture with ethyl acetate, filter, and concentrate under reduced pressure. Purify the residue by rapid chromatography. The yield of 4-(1-((diphenylmethylene)amino)-4-(trimethylsilyl)butyl)phenylacetate was 62%. 1 H NMR (400 MHz, CDCl3) δ 7.77–7.68 (m, 2H), 7.52–7.46 (m, 3H), 7.45–7.36 (m, 5H), 7.13 (q, J =3.1 Hz, 2H), 7.09 (d, J =8.2 Hz, 2H), 4.44 (dd, J=8.3, 5.0Hz, 1H), 2.35 (s, 3H), 2.10–1.96 (m, 1H), 1.90–1.78 (m, 1H), 1.38–1.31 (m,1H), 1.26–1.15 (m, 1H), 0.46 (t, J =8.4 Hz, 2H), 0.00 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 169.67, 166.63, 149.28, 143.10, 140.14, 137.24, 130.18, 129.95, 129.16, 128.65, 128.41, 128.11, 127.99, 121.31, 65.97, 43.64, 21.28, 21.01, 16.53, -1.48. Example 8: Synthesis of 1-(4-methoxyphenyl)-4-(trimethylsilyl)butan-1-amine [1-(4-methoxyphenyl)-4-(trimethylsilyl)butan-1-amine] (3h); Accurately weigh 40.4 μL (0.3 mmol), benzophenone O-(3-(trimethylsilyl)propionyl)oxime (146.5 mg, 0.45 mmol), and thioxanthone-9-one (0.3 mg, 0.00015 mmol) into an 8 mL reaction flask, followed by 3.0 mL of ethyl acetate. The resulting mixture was stirred for 10 hours at room temperature under blue LEDS (390 nm, 40 W). After the reaction was complete, the reaction mixture was diluted with ethyl acetate, filtered, and concentrated under reduced pressure. 3 mL of tetrahydrofuran and 3 mL of 1 M hydrochloric acid solution were added, and the mixture was stirred at room temperature for 3 h. The residue was extracted, alkalized, dried, and concentrated under reduced pressure. The residue was purified by rapid chromatography. The yield of 1-(4-methoxyphenyl)-4-(trimethylsilyl)butylamine was 58%. 1 H NMR (400MHz, CDCl3) δ 7.25–7.13 (m, 2H), 6.91–6.81 (m, 2H), 3.85 (t, J=6.9 Hz, 1H), 3.79(s, 3H), 1.77 (s, 2H), 1.70–1.58 (m, 2H), 1.41–1.16 (m, 2H), 0.54–0.43 (m,2H), -0.06 (s, 9H). 13 C NMR (101 MHz, CDCl3) δ 158.54, 138.88, 127.42, 113.85, 55.43, 55.36, 43.63, 21.09, 16.69, -1.53. Example 9: Synthesis of N-(1-(naphthalen-2-yl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine [N-(1-(naphthalen-2-yl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethanimine] (3i); Accurately weigh 46.3 mg (0.3 mmol) of 2-naphthylethylene, 146.5 mg (0.45 mmol) of benzophenone O-(3-(trimethylsilyl)propionyl)oxime, and 0.3 mg (0.00015 mmol) of thioxanthone-9-one into an 8 mL reaction flask, followed by 3.0 mL of ethyl acetate. The resulting mixture was stirred for 6 hours at room temperature under blue LEDS (390 nm, 20 W) irradiation. After the reaction was complete, the reaction mixture was diluted with ethyl acetate, filtered, and concentrated under reduced pressure. The residue was purified by rapid chromatography. The yield of N-(1-(naphth-2-yl)-4-(trimethylsilyl)butyl)-1,1-diphenylmethylene was 56%. 1 H NMR (400 MHz, CDCl3) δ 7.87–7.79 (m, 3H), 7.75 (m, 2H), 7.70 (s, 1H), 7.59(dd, J =8.5, 1.7 Hz, 1H), 7.50–7.44 (m, 5H), 7.42–7.34 (m, 3H), 7.11 (dd, J =6.5, 2.8 Hz, 2H), 4.58 (dd, J=8.2, 5.1 Hz, 1H), 2.19–2.03 (m, 1H), 2.01–1.87 (m,1H), 1.41–1.33 (m, 1H), 1.28–1.18 (m, 1H), 0.46 (dd, J =9.4, 7.5 Hz, 2H), -0.03(s, 9H). 13 C NMR (101 MHz, CDCl3) δ 166.04, 155.88, 155.46, 140.27, 137.33, 133.66, 132.70, 130.01, 128.77, 128.48, 128.43, 128.16, 128.07, 128.01, 127.97, 127.74, 125.89, 125.85, 125.41, 66.72, 43.54, 21.14, 16.58, -1.45. Example 10: Synthesis of 1,1-diphenyl-N-(1-(pyridin-2-yl)-4-(trimethylsilyl)butyl)methanimine [3j]; Accurately weigh 2-vinylpyridine (33 μL, 0.3 mmol), benzophenone O-(3-(trimethylsilyl)propionyl)oxime (146.5 mg, 0.45 mmol), and thioxanth-9-one (0.3 mg, 0.00015 mmol) into an 8 mL reaction flask, followed by 3.0 mL of dichloromethane. Stir the resulting mixture at room temperature under blue LEDS (390 nm, 40 W) irradiation for 6 hours. After the reaction was complete, dilute the reaction mixture with ethyl acetate, filter, and concentrate under reduced pressure. Purify the residue by rapid chromatography. The yield of 1,1-diphenyl-N-(1-(pyridin-2-yl)-4-(trimethylsilyl)butyl)methylimine was 58%. 1 H NMR (400 MHz, CDCl3) δ 8.51 (ddd, J =4.9, 1.9, 0.9 Hz, 1H), 7.76–7.68 (m,2H), 7.64 (td, J =7.7, 1.9 Hz, 1H), 7.55 (dt, J=7.9, 1.2 Hz, 1H), 7.43–7.32 (m,6H), 7.15–7.03 (m, 3H), 4.62 (dd, J =7.8, 5.3 Hz, 1H), 2.05–1.90 (m, 2H), 1.37–1.25 (m, 1H), 1.23–1.12 (m, 1H), 0.48–0.36 (m, 2H), -0.08 (s, 9H). 13 C NMR (101MHz, CDCl3) δ 167.78, 164.44, 148.90, 140.18, 136.90, 136.53, 130.04, 128.75,128.49, 128.12, 127.99, 124.80, 121.83, 121.72, 77.48, 77.16, 76.84, 68.15,42.40, 20.91, 16.56, -1.54.

Claims

1. A method for the photocatalytic synthesis of σ-aminosilicon, characterized in that, A series of aminosilane compounds were prepared under light irradiation using olefins and silyl oxime esters as raw materials; the synthetic route is as follows: The steps are as follows: Photocatalyst, olefin, silyl oxime ester, and solvent were added sequentially to the reaction flask, and the reaction flask was irradiated under blue light. R of olefins 1 It is an aromatic ring or a cyano group, wherein the aromatic ring is a phenyl group whose para position is further replaced by a halogen, trifluoromethyl, phenyl, carboxyl, methoxy, or formyl group, or the aromatic ring is a naphthyl ring or a pyridine ring; R of silyl oxime esters 2 R 3 R 4 It is a benzene ring or a methyl group; The concentration of olefins in the system is 0.1 M-0.3 M; The molar ratio of olefin to silyl oxime ester is 1:1.0 to 1:2.0; The molar ratio of olefin to photocatalyst is 1:0.01 to 1:0.1; The reaction time range is 2 to 18 hours; The intensity of blue light is 10 W-40 W; Blue light has a wavelength of 390 nm-456 nm.

2. The method for photocatalytic synthesis of σ-aminosilicon according to claim 1, characterized in that, The solvent is toluene, n-hexane, tetrahydrofuran, 1,4-dioxane, N,N -Dimethylformamide, N,N - One or more of dimethylacetamide, ethyl acetate, dichloromethane, acetone, and acetonitrile.

3. The method for photocatalytic synthesis of σ-aminosilicon according to claim 1, characterized in that, The photocatalyst is thioxanth-9-one, thioxanth-9-one derivatives, 2,4,5,6-tetra(9-carbazolyl)-isophthalonitrile, or tris-(2-phenylpyridine)iridium.

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