A catalyst-free, light-driven method for the synthesis of sulfinamide compounds

Abstract

This invention discloses a catalyst-free, light-driven method for the synthesis of sulfinamide compounds, which has wide applications in organic synthesis, pesticides, pharmaceuticals, and materials science. Using alkyl alcohols and sulfinimides as reactants, this invention synthesizes a series of sulfinamide derivatives with diverse functional groups through a deoxyalkylation reaction driven solely by blue light. In this reaction, alcohols, as alkyl sources, are readily available and widely sourced chemicals. Furthermore, the use of visible light as the sole driving force eliminates the need for expensive photocatalysts, making the entire reaction process greener and more efficient. This invention provides a new approach for the efficient synthesis of sulfinamides, featuring mild reaction conditions, convenient experimental operation, good substrate compatibility, and easy scale-up, thus possessing significant application value and socio-economic benefits.

Description

Technical Field

[0001] This invention relates to a method for preparing pharmaceutical and chemical intermediates, specifically a catalyst-free, light-driven method for reacting alcohol deoxygenation with sulfinylimide to generate sulfinamide. Background Technology

[0002] Sulfanamides are an important class of sulfur-containing compounds widely used in organic synthesis, pesticides, pharmaceuticals, and materials science. In organic synthesis, sulffanamides are important intermediates for the formation of sulfur-containing compounds such as sulfonamides, sulfoxide imides, sulfonylimides, and sulfonylimide esters. Furthermore, sulffanamides possess a chiral sulfur atom, exhibiting conformational stability, making them an important tool in asymmetric synthesis. In addition, the sulffanamide skeleton is also an important pharmacophore, accounting for up to 10% of FDA-approved drugs and widely found in antitumor and antiviral drugs.

[0003] Traditional synthetic routes for sulfinamides mainly rely on nucleophilic substitution reactions between amines and sulfinyl chlorides (Furukawa, M.; Okawara, T. Convenient Syntheses of Sulfinamide Derivatives. Synthesis 1976, 339-340). In recent years, coupling reactions of arylboronic acids with DAST-type reagents and copper-mediated transsulfinamide reactions have also been developed (Wang, Q.; Tang, X.; Shi, M. Metal-Free Cross-Coupling of Arylboronic Acids and Derivatives with DAST-Type Reagents for Direct Access to Diverse Aromatic Sulfinamides and Sulfonamides. Angew. Chem. Int. Ed., 2016, 55, 10811-10815.). However, the above-mentioned synthetic methods generally suffer from drawbacks such as difficult-to-obtain and unstable reagents, complex reaction systems, and harsh reaction conditions. There is an urgent need to develop a new method with simple and readily available raw materials, mild reaction conditions, and good functional group compatibility.

[0004] This invention is inspired by a paper published in the Journal of the American Chemical Society in 2023 by Michael C. Willis's research group at the University of Oxford, UK (Jonathan AA; Jagadeesh K.; Christopher FP; Darren LP; Kirsten EC; and Michael CW, Photocatalytic Carboxylate to Sulfinamide Switching Delivers a Divergent Synthesis of Sulfonamides and Sulfonimidamides. J. Am. Chem. Soc., 2023, 145(39), 21623-21629.). This method uses readily available and structurally diverse alkyl carboxylic acids as starting materials, and uses acridine photocatalysts and 400 nm light to generate alkyl radicals from carboxylic acids. The radicals are then added to sulfinamide reagents to produce sulfinamides. Based on the above research, this invention attempts to use alkyl alcohols as starting materials and sulfinyl imide as reactants. In the early stages of this invention's research, organic and inorganic photocatalysts were added to participate in the reaction. In the exploration of reaction conditions, it was found that not using a photocatalyst had no effect on the reaction.

[0005] This invention proposes a novel light-driven synthesis of sulfinamide compounds using alkyl alcohols and sulfinylimides as reactants under catalyst-free conditions. In this technique, the reactant alcohol is a widely available and readily accessible bulk chemical; simultaneously, the other raw material, sulfinylimide, is easy to prepare, has good stability, and is not easily decomposed, making it an ideal sulfinamide reagent; finally, the reaction in this invention only requires visible light to drive the process, eliminating the need for any external photocatalyst, thus making the entire process more green and efficient. Summary of the Invention

[0006] This invention provides a novel method for synthesizing sulfinamide compounds, which involves a one-pot in-situ conversion of alkyl alcohols into alkyl xanthates, followed by reaction with trivalent phosphine compounds and sulfinylimides under light conditions to generate sulfinamides. This invention offers advantages such as mild reaction conditions, convenient experimental operation, good substrate compatibility, and ease of scale-up, laying a solid foundation for further industrial applications and socio-economic value creation.

[0007] The technical solution of this invention:

[0008] A catalyst-free, light-driven method for the synthesis of sulfinamide compounds involves using alkyl alcohols (1), potassium tert-butoxide, and carbon disulfide as starting materials to generate alkyl xanthates (1') in situ via a one-pot process. These xanthates are then reacted with trivalent phosphine compounds and sulfinylimides (2) under light irradiation to prepare a series of sulfinamide compounds (3). The synthetic route is as follows:

[0009]

[0010] In the formula: R is selected from alkanes, alkenes, aryl groups and heterocycles, and alkyl alcohols are selected from primary alcohols, secondary alcohols and tertiary alcohols;

[0011] The steps are as follows:

[0012] (1) Using alkyl alcohol (1) and potassium tert-butoxide as starting materials, THF as solvent, the molar ratio of alkyl alcohol, potassium tert-butoxide and CS2 is 1:1.2:3, and the reaction concentration is 0.1 mol / L. Stir at room temperature for 30-60 minutes, then add CS2 and react at 0℃ for 2-3 hours to generate alkyl xanthate (1') in situ in a one-pot method;

[0013] (2) Under light conditions, alkyl xanthate (1') reacts with trivalent phosphine compound and sulfinimide (2) in a solvent to prepare a series of sulfinamide compounds (3);

[0014] Trivalent phosphine compounds are selected from tricyclohexylphosphine, dicyclohexylphenylphosphine, DPPE, tri-tert-butylphosphine, triphenylphosphine, 1,3-bis(dicyclohexylphosphine)butane and n-butylbis(1-adamantyl)phosphine.

[0015] The wavelength range is 390nm to 456nm.

[0016] The photoreaction time ranges from 8 to 24 hours, with 12 to 18 hours being preferred.

[0017] The solvent is selected from one or more of toluene, n-hexane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, dichloromethane, acetone, acetonitrile, ethanol, and methanol, preferably ethanol, acetonitrile, and acetone.

[0018] The concentration of alkyl xanthates in organic solvents is 0.075 mmol / mL to 0.3 mmol / mL.

[0019] The molar ratio of the alkyl xanthate to the sulfinimide is 1:1 to 1:2.

[0020] The molar ratio of the alkyl xanthate to the trivalent phosphine compound is 1:1 to 1:2.

[0021] The beneficial effects of this invention are as follows: This invention provides a novel method for preparing sulfinamides, achieving for the first time a photocatalyst-free, photocatalytically-driven deoxygenation coupling reaction between alkyl alcohols and sulfinamides, filling a gap in existing technologies. The method of this invention features mild process conditions, a short process flow, simple steps, a wide range of applicable substrates, easy scale-up, and a yield as high as 82%, meeting the needs of industrial production. Furthermore, the sulfinamides generated in the reaction have broad application prospects in organic synthesis and drug development. In summary, this invention has significant application value. Attached Figure Description

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

[0023] Figure 2 For compound 3a 13 C-NMR spectrum.

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

[0025] Figure 4 For compound 3b 13 C-NMR spectrum.

[0026] Figure 5 For compound 3c 1 H-NMR spectrum.

[0027] Figure 6 For compound 3c 13 C-NMR spectrum.

[0028] Figure 7 For compound 3d 1 H-NMR spectrum.

[0029] Figure 8 For compound 3d 13 C-NMR spectrum.

[0030] Figure 9 For compound 3e 1 H-NMR spectrum.

[0031] Figure 10 For compound 3e 13 C-NMR spectrum.

[0032] Figure 11 For compound 3f 1 H-NMR spectrum.

[0033] Figure 12 For compound 3f 13 C-NMR spectrum.

[0034] Figure 13 3g of compound 1 H-NMR spectrum.

[0035] Figure 14 3g of compound 13 C-NMR spectrum.

[0036] Figure 15 3g of compound 19 F-NMR spectrum.

[0037] Figure 16 For compound 3h 1 H-NMR spectrum.

[0038] Figure 17 For compound 3h 13 C-NMR spectrum.

[0039] Figure 18 For compound 3i 1 H-NMR spectrum.

[0040] Figure 19 For compound 3i 13 C-NMR spectrum.

[0041] Figure 20 For compound 3j 1 H-NMR spectrum.

[0042] Figure 21 For compound 3j 13 C-NMR spectrum.

[0043] Figure 22 For compound 3k 1 H-NMR spectrum.

[0044] Figure 23 For compound 3k 13 C-NMR spectrum. Detailed Implementation

[0045] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

[0046] Example 1: Synthesis of 2-phenyl-N-tritylethane-1-sulfinamide (3a)

[0047]

[0048] Weigh out phenylethanol (36.7 mg, 0.3 mmol) and KO in the glove box. tBu (40.4 mg, 0.36 mmol) and dry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, n-butyldi(1-adamantyl)phosphine and acetonitrile (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 16 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3a was 82%.

[0049] 1 H NMR (400MHz, CDCl3) δ7.30-7.24(m,17H),7.22-7.20(m,1H),7.16-7.14(m,2H),4.89(s,1H),3.06-2.91(m,4H). 13 C NMR (101MHz, CDCl3) δ 144.74, 139.02, 129.11, 128.68, 128.49, 128.00, 127.33, 126.58, 72.83, 58.25, 29.14. This product is a known compound.

[0050] Example 2: Synthesis of 3-(4-methoxyphenyl)-N-tritylpropane-1-sulfinamide (3b)

[0051]

[0052] Weigh 49.9 mg (0.3 mmol) of 3-(4-methoxybenzyl)-1-propanol and KO in a glove box. t Bu (40.4 mg, 0.36 mmol) was stirred with dry THF (3.0 mL) at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, tricyclohexylphosphine and acetonitrile (5 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (440 nm) for 14 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3b was 65%.

[0053] 1H NMR(400MHz, CDCl3)δ7.26-7.16(m,15H),6.95(d,J=8.6Hz,2H),6.74(d,J=8.6Hz,2H), 4.82(s,1H),3.70(s,3H),2.63(t,J=7.5Hz,2H),2.57-2.49(m,2H),1.91-1.84(m,2H). 13 C NMR (101MHz, CDCl3) δ157.96,144.78,132.53,129.32,129.15,127.94,127.30,113.85,72.84,56.61,55.19,33.45,25.06.HRMS m / z(ESI)calcd for C 29 H 29 NO2S(MH) + 454.1840, found 454.1847.

[0054] Example 3: Synthesis of (E)-3-phenyl-N-tritylprop-2-ene-1-sulfinamide (3c)

[0055]

[0056] Weigh out cinnamyl alcohol (40.3 mg, 0.3 mmol) and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) and dry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinimide, dicyclohexylphenylphosphine and ethanol (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 12 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3C was 56%.

[0057] 1 H NMR (400MHz, CDCl3) δ7.39-7.24(m,20H),6.56(d,J=15.9Hz,1H),6.38-6.31(m,1H),5.11(s,1H),3.72-3.67(m,1H),3.33-3.27(m,1H). 13 C NMR (101MHz, CDCl3) 13C NMR(101MHz,Chloroform-d)δ144.85,138.57,135.97,129.03,128.65,128.26,128.05,127.34,126.56,116.54,72.68,59.84.HRMS m / z(ESI)calcd for C 28 H 25 NOS(M+Na) + 446.1557, found 446.1555.

[0058] Example 4: Synthesis of 2-(4-bromophenyl)-N-tritylethane-1-sulfinamide (3d)

[0059]

[0060] Weigh out 60.3 mg (0.3 mmol) of p-bromophenylethanol and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) was stirred with ultradry THF (3.0 mL) at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, tert-butyldicyclohexylphosphine and acetone (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 16 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of the product was 60% over 3 days.

[0061] 1 H NMR (400MHz, CDCl3) δ7.38 (d, J = 8.4Hz, 2H), 7.32-7.25 (m, 15H), 7.01 (d, J = 8.4Hz, 2H), 4.86 (s, 1H), 3.00-2.85 (m, 4H). 13 C NMR(101MHz, CDCl3)δ144.68,137.96,131.74,130.24,129.06,128.04,127.39,120.44,72.88,58.03,28.68.HRMS m / z(ESI)calcd for C 27 H 24 BrNOS(M+Cl) - 526.0436, found 526.0424.

[0062] Example 5: Synthesis of Tert-butyl(4-(2-((tritylamino)sulfinyl)ethyl)phenyl)carbamate(3e)

[0063]

[0064] Weigh out N-Boc-2-(4-aminophenyl)ethanol (71.2 mg, 0.3 mmol) and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) and ultradry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, n-butyldi(1-adamantyl)phosphine and acetonitrile (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (440 nm) for 16 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3e was 65%.

[0065] 1 H NMR (400MHz, CDCl3) δ7.27-7.22(m,17H),7.03(d,J=7.9Hz,2H),6.48(s,1H),4.84(s,1H),2.96-2.83(m,4H),1.48(s,9H). 13 C NMR (101MHz, CDCl3) δ144.75,136.93,133.49,129.08,129.01,128.02,127.33,118.82,72.80,58.33,28.44,28.32.HRMS m / z(ESI)calcd for C 32 H 34 N₂O₃S(MH) + 525.2212, found 525.2206.

[0066] Example 6: Synthesis of N-tritylhexane-1-sulfinamide (3f)

[0067]

[0068] Weigh out n-hexanol (30.7 mg, 0.3 mmol) and KO in the glove box. tBu (40.4 mg, 0.36 mmol) and ultradry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, n-butyldi(1-adamantyl)phosphine and acetone (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 10 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3f was 84%.

[0069] 1 H NMR (400MHz, CDCl3) δ7.29-7.14(m,15H),4.86(s,1H),2.62-2.55(m,2H),1.57-1.49(m,2H),1.25-1.11(m,6H),0.77(t,J=6.7Hz,3H). 13 C NMR(101MHz, CDCl3)δ144.84,129.12,127.87,127.20,72.73,57.52,31.23,28.14,23.16,22.26,13.87.HRMS m / z(ESI)calcd for C 25 H 29 NOS(MH) + 390.1892, found 390.1887.

[0070] Example 7: Synthesis of 2-chloro-1-phenoxyallyl pivalate (3g)

[0071]

[0072] Weigh out 38.4 mg of 4,4,4-trifluorobutanol (0.3 mmol) and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) and ultradry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, n-butyldi(1-adamantyl)phosphine and ethanol (4 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 16 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of the product was 49% for 3 g.

[0073] 1 H NMR (400MHz, CDCl3) δ7.32-7.25(m,15H),5.01(s,1H),2.79-2.68(m,2H),2.17-2.05(m,2H),1.90(q,J=7.5Hz,2H). 13 C NMR (101MHz, CDCl3) δ144.63,129.11,128.05,127.45,72.96,55.80,32.60,32.31,16.67,16.64. 19 F NMR(377MHz,CDCl3)δ-66.11,-66.13,-66.16.HRMS m / z(ESI)calcd for C 23 H 22 F3NOS(MH) + 416.1296, found 416.1310.

[0074] Example 8: Synthesis of N-trityltetrahydro-2H-pyran-4-sulfinamide (3h)

[0075]

[0076] Weigh out tetrahydropyran-4-ol (30.6 mg, 0.3 mmol) and KO in a glove box. t Bu (40.4 mg, 0.36 mmol) was stirred with ultradry THF (3.0 mL) at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, tricyclohexylphosphine and acetonitrile (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (390 nm) for 12 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of the product after 3 hours was 68%.

[0077] 1 H NMR (400MHz, CDCl3) δ7.43–7.19(m,15H),4.80(s,1H),4.03(m,2H),3.39(td,J= 11.6,2.4Hz,2H),2.77(tt,J=11.7,4.1Hz,1H),1.92(m,2H),1.81–1.59(m,2H). 13C NMR(101MHz, CDCl3)δ144.66,129.34,127.92,127.38,73.00,66.95,66.83,61.33,26.58,26.21.HRMS m / z(ESI)calcd for C 24 H 25 NO2S(MH) + 390.1528, found 390.1538.

[0078] Example 9: Synthesis of N-tritylcyclohexanesulfinamide (3i)

[0079]

[0080] Weigh out cyclohexanol (30.1 mg, 0.3 mmol) and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) and ultradry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, n-butyldi(1-adamantyl)phosphine and acetonitrile (5 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 12 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3i was 86%.

[0081] 1 H NMR (400MHz, CDCl3) δ7.56-7.04(m,15H),4.77(s,1H),2.51(tt,J=11.3,3.7Hz,1H),2.09- 1.95(m,2H),1.82(tt,J=16.6,3.8Hz,2H),1.64(dd,J=11.2,5.0Hz,1H),1.50-1.14(m,5H). 13 C NMR (101MHz, CDCl3) δ 144.88, 129.32, 127.85, 127.23, 72.80, 64.13, 26.67, 25.52, 25.45, 25.36, 25.17. The product is a known compound.

[0082] Example 10: Synthesis of (3s,5s,7s)-N-trityladamantane-1-sulfinamide (3j)

[0083]

[0084] Weigh out 45.7 mg (0.3 mmol) of 1-adamantanol and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) was stirred with ultradry THF (3.0 mL) at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, dicyclohexylphenylphosphine and ethanol (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 16 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3j was 59%.

[0085] 1 H NMR (400MHz, CDCl3) δ7.36-7.22(m,15H),4.59(s,1H),2.20-2.11(m,3H),1.95-1.87(m,3H),1.85-1.78(m,3H),1.78-1.63(m,6H). 13 C NMR (101MHz, CDCl3) δ 145.03, 129.55, 127.82, 127.26, 72.65, 58.95, 36.42, 35.21, 28.72. The product is a known compound.

[0086] Example 11: Synthesis of 2-methyl-N-tritylhexane-2-sulfinamide (3k)

[0087]

[0088] Weigh out 34.8 mg of 2-methyl-2-hexanol (0.3 mmol) and KO in a glove box. t Bu (40.4 mg, 0.36 mmol) and ultradry THF (3.0 mL) were stirred at room temperature for 30 minutes, and then CS2 (54.1 μL, 0.9 mmol) was added at 0°C and reacted for 3 hours. After the reaction was completed, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, 1,3-bis(dicyclohexylphosphino)butane and acetonitrile (3 mL) were added in sequence. The resulting mixture was stirred at room temperature under blue LED light (456 nm) for 18 hours. After the reaction was completed, the mixture was filtered with diatomaceous earth, dried by vacuum pump, and then separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3k was 58%.

[0089] 1H NMR (400MHz, CDCl3) δ7.37-7.17(m,15H),4.52(s,1H),1.69-1.57(m,1H),1. 53-1.38(m,1H),1.35-1.23(m,4H),1.20(d,J=7.0Hz,6H),0.91-0.83(m,3H). 13 C NMR(101MHz, CDCl3)δ144.94,129.58,127.79,127.29,72.87,60.34,36.09,25.70,23.25,20.09,19.95,13.91.HRMS m / z(ESI)calcd for C 26 H 31 NOS(MH) + 404.2048, found 404.2043.

[0090] Example 12: Synthesis of 2-phenyl-N-tritylethane-1-sulfinamide (3a) (with photocatalyst)

[0091]

[0092] Weigh out phenylethanol (36.7 mg, 0.3 mmol) and KO in the glove box. t Bu (40.4 mg, 0.36 mmol) and dry THF (3.0 mL) were stirred at room temperature for 30 minutes, followed by the addition of CS2 (54.1 μL, 0.9 mmol) at 0°C for 3 hours. After the reaction was complete, the solvent was removed by vacuum distillation to obtain xanthate. Then, sulfinylimide, n-butyldi(1-adamantyl)phosphine, 4CzIPN, and acetonitrile (3 mL) were added sequentially. The resulting mixture was stirred at room temperature under a blue LED lamp (456 nm) for 16 hours. After the reaction was complete, the mixture was filtered through diatomaceous earth, dried under vacuum, and separated by silica gel column chromatography using petroleum ether / ethyl acetate as eluent. The yield of product 3a was 83%. The yield with and without the photocatalyst was not significantly increased, therefore, this reaction does not require a photocatalyst.

Claims

1. A catalyst-free, light-driven synthesis method for sulfinamide compounds, characterized in that, Alkyl alcohol (1), potassium tert-butoxide, and carbon disulfide were used as starting materials to generate alkyl xanthate (1') in situ via a one-pot method. Then, under light irradiation, these xanthates were reacted with trivalent phosphine compounds and sulfinyl imides to prepare a series of sulfinamide compounds (3). The synthetic route is as follows: ； In the formula: R is selected from one of the alkanes; The steps are as follows: (1) Using alkyl alcohol and potassium tert-butoxide as starting materials and THF as solvent, stir at room temperature for 30-60 minutes, then add CS2 and react at 0 °C for 2-3 hours to generate alkyl xanthate in situ in one pot; The molar ratio of alkyl alcohol, potassium tert-butoxide, and CS2 is 1:1.2:3, and the reaction concentration is 0.1 mol / L. (2) Under light irradiation, alkyl xanthate, trivalent phosphine compound, and sulfinimide react in a solvent to prepare a series of sulfinamide compounds, wherein the sulfinimide is... ; The concentration of alkyl xanthate in the solvent is 0.075 mmol / mL ~ 0.3 mmol / mL; The molar ratio of alkyl xanthate to sulfinimide is 1:1 to 1:2; The molar ratio of alkyl xanthate to trivalent phosphine compound is 1:1 to 1:

2. Trivalent phosphine compounds are selected from tricyclohexylphosphine, dicyclohexylphenylphosphine, DPPE, tri-tert-butylphosphine, triphenylphosphine, 1,3-bis(dicyclohexylphosphine)butane and n-butylbis(1-adamantyl)phosphine.

2. The method according to claim 1, characterized in that, Alkyl alcohols are selected from primary alcohols, secondary alcohols, and tertiary alcohols.

3. The method according to claim 1, characterized in that, The solvent is one or a mixture of two or more of the following: toluene, n-hexane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, dichloromethane, acetone, acetonitrile, ethanol, and methanol.

4. The method according to claim 1, characterized in that, The wavelength range of the illumination is 390 nm to 456 nm.

5. The method according to claim 1, characterized in that, The photoreaction time is 8 to 24 hours.

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