Method for preparing borylated carbonyl derivative

Abstract

The invention relates to a method for preparing a boronized carbonyl derivative by catalyzing an alpha, beta-unsaturated carbonyl derivative with a heterogeneous photocatalyst, which comprises the following steps: by taking the alpha, beta-unsaturated carbonyl derivative and N-heterocyclic carbene borane as raw materials and cadmium sulfide as the heterogeneous photocatalyst, reacting for 1-100 hours at 0-80 DEG C in an inert atmosphere and under the illumination condition, thereby obtaining the boronized carbonyl derivative. The product borylated carbonyl derivative is obtained. The alpha-boron substituted compound is prepared by adopting the heterogeneous photocatalyst for the first time, the reaction condition is mild, and the catalyst can be recycled.

Description

Technical Field

[0001] The invention belongs to the field of catalysis, and in particular relates to a method for preparing a borylated carbonyl derivative by catalyzing an alpha, beta-unsaturated carbonyl derivative with a heterogeneous photocatalyst. Background Art

[0002] Organoboron compounds have very wide applications in materials science, synthetic chemistry, life sciences and other fields. Therefore, studying how to efficiently construct carbon-boron bonds has always been the focus and hotspot in synthetic chemistry. Carbon-boron bond formation reactions usually use biboronic acid pinacol ester (B2Pin2), pinacol borane (HBPin), catechol borane (HBCat) and the like as boron reagents. Compared with traditional boron reagents, nitrogen heterocyclic carbene (NHC) borane has the advantages of being easy to obtain, highly stable and easy to operate. In addition, due to the presence of coordination bonds in NHC borane, a push-pull electron structure is formed between NHC and borane, and the boron center is converted from sp2 hybridization to sp3 hybridization, resulting in a significant increase in the electron cloud density of the boron center. It is precisely because of its unique electronic structure that it exhibits a different reactivity from traditional borane reagents. Therefore, the synthesis of organoboron compounds involving NHC borane has received more and more attention.

[0003] In the past few decades, heterogeneous photocatalysis has become a comprehensive research field due to its great potential in solving environmental pollution and the world energy crisis. Based on its characteristics of using renewable solar energy as a driving force and mild reaction conditions, heterogeneous photocatalysis has become an important part of modern chemistry in the 21st century.

[0004] As a powerful means to efficiently construct complex organic compounds, free radical reactions have the advantages of mild reaction conditions, fast reaction rates, and good functional group tolerance. Therefore, the synthesis of organoboron compounds using free radical reactions has attracted widespread attention from researchers. At present, a series of progress has been made in the synthesis of organoboron compounds involving nucleophilic NHC boron radicals. For example, the free radical regioselective α- or β-borylation of α, β-unsaturated carbonyl compounds generates α-borylated carbonyl compound molecules, which provides a direct and practical route for the synthesis of borylated carbonyl compounds and solves the difficulty and time cost of multi-step synthesis in the previous preparation process of such compounds.

[0005] However, the methods for the free radical regioselective α- or β-borylation of α, β-unsaturated carbonyl compounds to generate α-boryl carbonyl compounds still have the following problems. 1) The reaction uses a homogeneous photoinitiator, the synthesis process is cumbersome, expensive, and cannot be recycled. (Dai, W. et al., Org. Lett. 2021, 23, 4353-4357.; Wang, Y.-F. et al., Angew. Chem. 10.

[0006] 1002 / ange.201915619.) 2) Diazo compounds are used as raw materials in the reaction process. Such compounds are unstable and explosive, which greatly limits the practical application of the reaction. (DPet al., J.Am.Chem.Soc.2013,135,12076–12081.; Zhou,Q.-L.et al., J.Am.Chem.Soc.2013,135,14094–14097.; Zhou,Q.-L.et al.,Acta Chim.Sin.

[0007] 2015,73,326–329.;Yang,J.-M.et al.ACS Catal.2018,8,7351–7355.;Xu,M.-HJAm.Chem.Soc.2015,137,5268–5271.;Arnold,FHNature2017,552,132.) 3) Use high-energy free radical initiators, such as azobisisobutyronitrile, in the reaction process. (Wang,Y.-F.et al.,Nature Communications.2019,10,1934.) Summary of the invention

[0008] As mentioned above, although there are many methods for preparing stable α-boron substituted compounds, they all use homogeneous photocatalysts, the preparation process is cumbersome, expensive, and cannot be recycled. The present invention aims at the deficiencies of the above-mentioned prior art and provides a method for selective hydroboration of α, β-unsaturated carbonyl compounds using heterogeneous catalysis.

[0009] The present invention is to prepare borylated carbonyl derivatives by regioselective direct addition of cheap and readily available nitrogen heterocyclic carbene (NHC) borane and α, β-unsaturated carbonyl derivative free radicals under the action of heterogeneous photocatalyst. The method has the following advantages: 1) the use of heterogeneous catalysts makes post-treatment simple and the catalyst is easy to separate and recover. 2) The substrate has a wide range of applications, and the applicable β-aryl-α, β-unsaturated esters, β-aryl-α, β-unsaturated amides, β-aryl-α, β-unsaturated nitriles, and β-alkyl-α, β-unsaturated esters can all achieve above-average yields. 3) The method has mild conditions and does not require the addition of additional initiators, organic bases, thiols and other reaction aids. It has the advantages of simple operation, high stability, and can achieve gram-level scale-up.

[0010] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0011] The method uses α, β-unsaturated carbonyl derivatives and N-heterocyclic carbene borane as raw materials, a heterogeneous cadmium sulfide photocatalyst, a molar ratio of the α, β-unsaturated carbonyl compound to the nitrogen heterocyclic carbene borane of 1:0.1-1:5, and a molar ratio of the α, β-unsaturated carbonyl compound to the organic photosensitizer of 1:0.001-1:0.5. After inert gas replacement, the reaction is carried out at 0-40°C for 1-100 hours under light source irradiation to obtain a borylated carbonyl derivative.

[0012] The α,β-unsaturated carbonyl derivative includes at least one of β-aryl-α,β-unsaturated ester, β-aryl-α,β-unsaturated amide, β-aryl-α,β-unsaturated nitrile and β-alkyl-α,β-unsaturated ester.

[0013] The nitrogen heterocyclic carbene borane is a compound having the following structure:

[0014]

[0015] The heterogeneous photocatalyst is a compound having the following structure, and the catalyst used is one or more of the following catalysts: nanosheet cadmium sulfide, nanorod cadmium sulfide, nanosphere cadmium sulfide, nanomesoporous sphere cadmium sulfide, nanowire cadmium sulfide, cadmium sulfide@C3N4, preferably nanosheet cadmium sulfide.

[0016] The inert gas is one or more of helium, nitrogen, and argon, preferably nitrogen. The light source is one of visible violet light (380nm-435nm), visible blue light (435nm-490nm), visible green light (490nm-560nm), and visible white light (380nm-780nm), preferably a visible white light source (380nm-780nm).

[0017] The light source power is 1W to 100W, preferably 5W to 50W.

[0018] The solvent may be one of ethanol, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, and dichloromethane, preferably acetonitrile.

[0019] The method for preparing borylated carbonyl derivatives of the present invention has the following advantages: 1) It is the first time to use a heterogeneous photocatalyst to prepare an α-boron substituted compound, the reaction conditions are mild, and the catalyst can be recycled. 2) The substrate has a wide range of applications, and all applicable substrates can achieve a medium or higher yield. 3) The method avoids the use of high-energy free radical initiators, organic bases, thiols and other reaction aids in the existing system. 4) The method has the advantages of simple operation, high stability, and can achieve gram-scale scale-up. DETAILED DESCRIPTION

[0020] The specific implementation steps of the present invention are described in detail below through some embodiments, but these embodiments should not be regarded as limiting the scope of the present invention.

[0021] The nitrogen heterocyclic carbene borane used in the following examples is a compound having the following structure,.

[0022]

[0023] Example 1

[0024] Synthesis of Nanosheet-Loaded CdS:

[0025] 2.0mmol cadmium acetate and 6.0mmol thiourea were uniformly dispersed in 60mL ethylenediamine, then transferred to 80mL polytetrafluoroethylene hydrothermal autoclave, heated at 100°C for 8 hours, then cooled to room temperature, washed with deionized water and ethanol three times respectively, and vacuum dried at 60°C for 12 hours to obtain 0.25g bright yellow solid. The flaky structure can be seen by JSM-7800F field emission scanning electron microscope, and the thickness can be analyzed by Raman-atomic force microscope combined imaging analysis system to 0.4-0.8nm, and the structure measured by X-ray powder diffractometer is cadmium sulfide hexagonal wurtzite crystal.

[0026] Example 2

[0027] Synthesis of nano-spherical cadmium sulfide:

[0028] 0.6mmol cadmium acetate and 15mmol thiourea were uniformly dispersed in 15mL deionized water, then transferred to a polytetrafluoroethylene hydrothermal reactor, heated at 140°C for 5 hours, then cooled to room temperature, washed with deionized water and ethanol three times respectively, and vacuum dried at 60°C for 12 hours to obtain 0.08g orange-yellow solid. The spherical structure can be seen by a JSM-7800F field emission scanning electron microscope, with a spherical diameter of 40 to 70nm, and the structure measured by an X-ray powder diffractometer is a cadmium sulfide hexagonal wurtzite crystal.

[0029] Example 3

[0030] Synthesis of Nanorod-Shaped Cadmium Sulfide:

[0031] 10mmol of cadmium nitrate and 30mmol of thiourea were dispersed in 50mL of ethylenediamine, then transferred to a polytetrafluoroethylene hydrothermal autoclave, heated at 160°C for 48 hours, then cooled to room temperature, washed with deionized water and ethanol three times respectively, and vacuum dried at 60°C for 12 hours to obtain 1.4g of yellow solid. A rod-like structure with a length of 20 to 40nm and a diameter of 0.1 to 1nm can be seen through a JSM-7800F field emission scanning electron microscope. The structure measured by an X-ray powder diffractometer is a hexagonal wurtzite crystal of cadmium sulfide.

[0032] Example 4

[0033] Synthesis of nanowire-shaped cadmium sulfide:

[0034] 1.6 g of cadmium nitrate and 1.19 g of urea were dispersed in 50 mL of ethylenediamine and stirred for 1 hour. The mixture was then transferred to a polytetrafluoroethylene hydrothermal reactor and heated at 180 ° C for 72 hours. It was then cooled to room temperature and washed with deionized water and ethanol three times respectively. It was vacuum dried at 60 ° C for 12 hours to obtain 0.6 g of yellow solid. A linear structure with a length of 150 to 300 nm and a diameter of 0.1 to 1 nm can be seen by a JSM-7800F field emission scanning electron microscope. The structure measured by an X-ray powder diffractometer is a hexagonal wurtzite crystal of cadmium sulfide.

[0035] Example 5

[0036] Synthesis of Nano-mesoporous Spherical Cadmium Sulfide

[0037] 1.6g of cadmium nitrate was dispersed in 80mL of ethylenediamine, 1g of PVP (polyvinyl pyrrolidone) and 0.4g of urea were added, stirred for 1 hour, and then the mixture was transferred to a polytetrafluoroethylene hydrothermal autoclave, heated at 160°C for 8 hours, then cooled to room temperature, washed with deionized water and ethanol three times respectively, and vacuum dried at 60°C for 12 hours to obtain 0.6g of yellow protective body. The spherical structure with a diameter of 50-60nm and a pore size of 0.01-0.5nm can be seen through a JSM-7800F field emission scanning electron microscope. The structure measured by an X-ray powder diffractometer is a hexagonal wurtzite crystal of cadmium sulfide.

[0038] Example 6

[0039] Synthesis of Cadmium Sulfide@C3N4:

[0040] 10g of urea was placed in a crucible, placed in a muffle furnace, and calcined at 550℃ for 3 hours at a heating rate of 5℃ / min to obtain a light yellow g-C3N4 solid. 0.5g of C3N4 was dispersed in 100mL of 5mol / L nitric acid solution, refluxed at 125℃ for 12 hours, then washed with water 5 times to remove nitric acid, and vacuum dried at 60℃ for 12 hours to obtain g-C3N4 nanosheets, which were analyzed by Raman-atomic force microscopy combined with imaging analysis system to have a thickness of 0.4-0.8nm.

[0041] 8 mg of g-C3N4 nanosheets were dispersed in 15 mL of methanol and sonicated for 1 hour, labeled as solvent A. At the same time, 92 mg of nanorod-shaped cadmium sulfide prepared in Example 3 was dispersed in 10 mL of methanol, labeled as solvent B. Solvent B was added dropwise to solvent A and stirred for an additional 24 hours. After that, it was washed with water three times and vacuum dried at 60°C for 12 hours to obtain 95 mg of solid.

[0042] Example 7

[0043] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide prepared in Example 1 (10 mg) and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 48.1 mg of the corresponding product (yield 84%).

[0044] 1H NMR (400MHz, CDCl3) δ7.23-7.16(m,4H),7.12-7.06(m,1H),6.80(s,2H),3.86-3.76(m,2H),3.74(s,6H 13C NMR (101MHz, CDCl3) δ181.65,144.85,128.54,127.83,124.98,120.33,58.56,39.12,36.04,29.70,14.32; 11B NMR(128MHz, CDCl3)δ-25.00(t,89.5Hz); HRMS(ESI)m / z[M+Na]+calculated for C16H23BN2NaO2 309.1750, found 309.1755.

[0045] Example 8

[0046] Methyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide (10 mg) prepared in Example 1 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 43.0 mg of the corresponding product (yield 79%).

[0047] 1H NMR (400MHz, CDCl3) δ7.22-7.15(m,4H),7.12-7.05(m,1H),6.80(s,2H),3.72(s,6H),3.3 7(s,3H),3.11(dd,J=14.2,10.2Hz,1H),2.71(dd,J=14.3,4.0Hz,1H),2.20(brs,1H); 13C NMR (101MHz, CDCl3) δ182.0,144.7,128.5,127.9,125.1,120.4,50.4,39.1,36.0; 11B NMR(128MHz, CDCl3)δ-25.02(t,J=90.2Hz); HRMS(ESI)m / z[M+Na]+calculated for C15H21BN2NaO2 295.1594, found 295.1593.

[0048] Example 9

[0049] Ethyl 4-methylcinnamate (0.20 mmol), azacyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide (10 mg) prepared in Example 1 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 16 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 39.5 mg of the corresponding product (yield 69%).

[0050] 1H NMR (400MHz, CDCl3) δ7.12(d,J=8.5Hz,2H),6.80(s,2H),6.77-6.73(m,2H),3.81(dtd,J=14.2,7.1,3.7Hz,2H),3.75(s 13C NMR (101MHz, CDCl3) δ181.68,157.18,137.11,129.37,120.31,113.28,58.51,55.22,38.23,36.05,14.35; 11B NMR (128MHz, CDCl3) δ-25.07 (t, J = 90.6Hz); HRMS (ESI) m / z [M+Na]+calculated for C17H25BN2NaO3 339.1856, found 339.1849.

[0051] Example 10

[0052] Ethyl 4-methoxycinnamate (0.20 mmol), azacyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide (10 mg) prepared in Example 1 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 48.1 mg of the corresponding product (yield 76%).

[0053] 1H NMR (400MHz, CDCl3) δ7.08(d,J=7.9Hz,2H),7.00(d,J=7.8Hz,2H),6.80(s,2H),3.72(s,6H),3.37 (s,3H),3.06(dd,J=14.2,10.4Hz,1H),2.66(dd,J=14.3,3.8Hz,1H),2.26(s,3H),2.18(s,1H); 13C NMR (101MHz, CDCl3) δ182.00,141.65,134.28,128.60,128.29,120.41,50.35,38.65,35.99,20.99; 11B NMR (128MHz, CDCl3) δ-25.01 (t, J = 90.0Hz); HRMS (ESI) m / z [M+Na]+calculated for C16H23BN2NaO2 309.1750, found309.1748.

[0054] Embodiment 11

[0055] Into an oven-dried borosilicate glass photoreaction tube with a magnet, methyl 3-(2-thiophene) propionate (0.20 mmol), azacyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide prepared in Example 1 (10 mg) and 2 mL of acetonitrile were added in sequence, placed in a photoreactor and sealed, the air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 36.7 mg of the corresponding product (yield 66%).

[0056] 1H NMR (400MHz, CDCl3) δ7.01(d,J=4.7Hz,1H),6.84(d,J=3.5Hz,1H),6.82(s,2H),6.75(d,J=2.4Hz,1H),3 .75(s,6H),3.43(s,3H),3.31(dd,J=15.2,10.3Hz,1H),2.90(dd,J=15.2,3.3Hz,1H),2.20(brs,1H); 13C NMR (101MHz, CDCl3) δ181.5,148.1,126.4,123.6,122.2,120.4,50.5,36.0,33.3; 11B NMR(128MHz, CDCl3)δ-25.18(t,J=90.6Hz); HRMS(ESI)m / z[M+Na]+calculated for C13H19BN2NaO2S 301.1158, found 301.1162.

[0057] Example 12

[0058] 2-Fluorocinnamonitrile (0.20 mmol), azacyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide (10 mg) prepared in Example 1 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using a mixed solvent of ethyl acetate / n-hexane as the eluent (V:V=1:1) to obtain 36.5 mg of the corresponding product (yield 71%).

[0059] 1H 13C 11B NMR(128MHz, CDCl3)δ-25.96(t,J=90.5Hz); 19F NMR(376MHz, CDCl3)δ-106.2–-126.3(m); HRMS(ESI)m / z[M+H]+calculated for C14H18BFN3258.1578, found 258.1579.

[0060] Embodiment 13

[0061] Methyl 2-pentenoate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide (10 mg) prepared in Example 1 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 24 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using a mixed solvent of ethyl acetate / n-hexane as the eluent (V:V=1:1) to obtain 37.2 mg of the corresponding product (yield 83%).

[0062] 1H NMR (400MHz, CDCl3) δ6.78(s,2H),3.75(s,6H),3.51(s,3H),2.28(dd,J=7.2,5.4Hz,1H ),2.04(dd,J=14.1,8.1Hz,1H),1.24(s,2H),1.02(brs,1H),0.84(t,J=7.3Hz,3H); 13C NMR(101MHz, CDCl3)δ177.1,120.1,50.8,41.8,36.0,30.0,13.2; 11B NMR(128MHz, CDCl3)δ-25.30(t,J=85.0Hz); HRMS(ESI)m / z[M+Na]+calculated forC11H21BN2NaO2 247.1594, found 247.1591.

[0063] Embodiment 14

[0064] 1-(4-morpholinyl)-3-phenyl-2-propene-1-one (0.20 mmol), azacyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide prepared in Example 1 (10 mg) and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 24 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using a mixed solvent of ethyl acetate / n-hexane as the eluent (V:V=1:1) to obtain 62.3 mg of the corresponding product (yield 95%).

[0065] 1H NMR (400MHz, CDCl3) δ7.19-7.08 (m, 4H), 7.05 (t, J = 7.0Hz, 1H), 6.81 (s, 2H), 3.72 (s, 6H), 3.61 -3.33(m,8H),3.01(dd,J=13.4,10.1Hz,1H),2.60(dd,J=13.6,3.9Hz,1H),2.53(brs,1H); 13C NMR (101MHz, CDCl3) δ180.3,145.0,128.4,127.8,124.9,120.6,67.3,67.0,46.1 ,41.7,39.1,36.3;11BNMR(128MHz,CDCl3)δ-26.09(t,J=87.7Hz);HRMS(ESI)m / z

[0066] [M+H]+calculated for C18H27BN3O2 328.2196, found 328.2200.

[0067] The above embodiments are partial implementation methods of the present invention, but the implementation methods of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

[0068] Embodiment 15

[0069] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanorod-shaped cadmium sulfide (10 mg) prepared in Example 3 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 51.4 mg of the corresponding product (yield 90%).

[0070] Example 16

[0071] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanowire cadmium sulfide (10 mg) prepared in Example 4 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 45.6 mg of the corresponding product (yield 80%).

[0072] Embodiment 17

[0073] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nano-spherical cadmium sulfide (10 mg) prepared in Example 2 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using a mixed solvent of ethyl acetate / n-hexane as the eluent (V:V=1:1) to obtain 50.2 mg of the corresponding product (yield 88%).

[0074] Embodiment 18

[0075] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), mesoporous nano-spherical cadmium sulfide (10 mg) prepared in Example 5 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 51.9 mg of the corresponding product (yield 91%).

[0076] Embodiment 19

[0077] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), cadmium sulfide prepared in Example 6 and the like were added to a borosilicate glass photoreaction tube with a magnet that had been dried in an oven.

[0078] @C3N4 (10 mg) and 2 mL of acetonitrile were placed in a photoreactor and sealed. The air above the tube was replaced with nitrogen three times. The reaction solution was irradiated with a 10 W white light source. After 8 hours of reaction, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 36.6 mg of the corresponding product (yield 64%).

[0079] Comparative Example 1

[0080] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide @C3N4 (10 mg) prepared in Example 6 and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with 10 W visible green light (490 nm-560 nm). After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using a mixed solvent of ethyl acetate / n-hexane as the eluent (V:V=1:1) to obtain 14.3 mg of the corresponding product (yield 25%).

[0081] Comparative Example 2

[0082] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), nanosheet cadmium sulfide @C3N4 (10 mg) prepared in Example 6 and 2 mL of tetrahydrofuran were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After reacting for 8 hours, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 5.7 mg of the corresponding product (yield 10%).

[0083] Comparative Example 3

[0084] Ethyl cinnamate (0.20 mmol), nitrogen heterocyclic carbene borane (0.22 mmol), C3N4 (10 mg) and 2 mL of acetonitrile were added to a borosilicate glass photoreaction tube dried in an oven and sealed. The air above the tube was replaced with nitrogen three times, and the reaction solution was irradiated with a 10 W white light source. After 8 hours of reaction, 11 The reaction progress was monitored by B-NMR, the solvent was removed by rotary evaporation, and the crude product was further purified by rapid column chromatography using ethyl acetate / n-hexane mixed solvent as eluent (V:V=1:1) to obtain 7.4 mg of the corresponding product (yield 13%).

[0085] It can be seen from the following examples and comparative examples that good yields can be obtained for different substrates using different catalysts of the present invention. It can be seen from comparative example 1 that the yield is reduced by changing the light source to a non-optimal light source. It can be seen from comparative example 2 that the yield is reduced by changing the solvent to a non-optimal solvent. It can be seen from comparative example 3 that the yield is reduced by changing the catalyst to a non-optimal catalyst.

Claims

1. A method for preparing a borylated carbonyl derivative, characterized in that: With α, β-unsaturated carbonyl derivatives and N-heterocyclic carbene borane as raw materials and cadmium sulfide as a heterogeneous photocatalyst, the reaction is carried out at 0-80° C. (preferably 10-50° C., more preferably 15-25° C.) for 1-100 h (preferably 5-80 h, more preferably 8-30 h) under inert atmosphere and light conditions to obtain a borylated carbonyl derivative.

2. The method according to claim 1, characterized in that The α,β-unsaturated carbonyl derivatives include at least one or more of β-aryl-α,β-unsaturated esters, β-aryl-α,β-unsaturated amides, β-aryl-α,β-unsaturated nitriles, and β-alkyl-α,β-unsaturated esters; β-Aryl-α,β-unsaturated esters include ethyl cinnamate, methyl cinnamate, propyl cinnamate, isopropyl cinnamate, butyl cinnamate, ethyl 4-cyanocinnamate, methyl 4-cyanocinnamate, ethyl 4-methoxycinnamate, methyl 4-methoxycinnamate, benzyl cinnamate, ethyl 3-pyridylacrylate, ethyl 3-(4-aminopyridin-3-yl)acrylate, methyl 3-(thiophene-2-yl)acrylate , cinnamate, coumarin, 4-methylcoumarin, 6-methylcoumarin, 7-methylcoumarin, diethyl benzylmalonate, diethyl benzoylmalonate, 1-(4-morpholinyl)-3-phenyl-2-propene-1-one, diethyl (1-phenylpropyl)malonate, ethyl 2-cyano-3,3-diphenylacrylate, and at least one or more of 2-cyano-3,3-diphenylacrylate; The β-aryl-α,β-unsaturated amide includes at least one or two or more of cinnamamide, (E)-N,N-diethyl-3-benzoylacetylene-2-enamine, 1-cinnamapiperazine, p-methylcinnamamide, 4-chlorocinnamamide, and N,N-diphenylcinnamamide; β-aryl-α,β-unsaturated nitrile includes at least one or two or more of 3-aminocinnamonitrile, p-methylcinnamonitrile, 3-(4-fluorophenyl)-2-propenenitrile, benzyl propiononitrile, 2H-chromene-3-carbonitrile, 4-methoxycinnamonitrile, 2-(1-phenylethylidene) propiononitrile, coumarin-3-nitrile, 4-fluorocinnamonitrile, 3-fluorocinnamonitrile, and 4-methylcinnamonitrile; The β-alkyl-α,β-unsaturated ester includes at least one or two or more of methyl crotonate, ethyl crotonate, benzyl crotonate, methyl 4-bromocrotonate, methyl 3-aminocrotonate, methyl 2-pentenoate, ethyl cyclopropylidene acetate, and methyl cyclopentene-1-carboxylate.

3. The method according to claim 1 or 2, characterized in that: The nitrogen heterocyclic carbene borane is a compound having the following structure, The molar ratio of the α,β-unsaturated carbonyl compound to the nitrogen heterocyclic carbene borane is 1:0.1 to 1:5, preferably 1:0.8 to 1:3, and more preferably 1:1 to 1:1.

5.

4. The method according to claim 1, characterized in that: The heterogeneous photocatalyst cadmium sulfide is a compound with the following structure, and the catalyst used is one or more of the following catalysts, at least one or more of nanosheet cadmium sulfide, nanorod cadmium sulfide, nanospherical cadmium sulfide, nanomesoporous spherical cadmium sulfide, nanowire cadmium sulfide, and cadmium sulfide@g-C3N4. The molar ratio of the α, β-unsaturated carbonyl compound to the heterogeneous photocatalyst is 1:0.001 to 1:0.8, preferably 1:0.005 to 1:0.5, and more preferably 1:0.01 to 1:0.

2.

5. The method according to claim 1, characterized in that: The inert atmosphere gas is one or more of helium, nitrogen and argon.

6. The method according to claim 1, characterized in that: The light source of the illumination is one or more of visible violet light (wavelength 380nm-435nm), visible blue light (wavelength 435nm-490nm), visible green light (wavelength 490nm-560nm), and visible white light (wavelength 380nm-780nm), preferably a visible white light source (wavelength 380nm-780nm).

7. The method according to claim 1 or 6, characterized in that: The light source power is 1W to 100W, preferably 5W to 50W.

8. The method according to claim 1, characterized in that The reaction is carried out in a solvent, which is one or more of ethanol, acetonitrile, 1,4-dioxane, N,N-dimethylformamide and dichloromethane.

9. The method according to any one of claims 1 to 8, characterized in that: Specifically, the method comprises the following steps: adding 0.2 mmol of α, β-unsaturated carbonyl derivative into a transparent photoreaction tube (such as a borosilicate glass photoreaction tube), adding 0.2-0.3 mmol of nitrogen heterocyclic carbene borane, 1-5 mL of solvent, and 1-20 mg of catalyst, replacing the air in the photoreaction tube with an inert atmosphere gas for 3-5 times, stirring under light irradiation, and directly rotating and evaporating the solvent when TLC shows that the raw material has been consumed, using a petroleum ether / ethyl acetate mixed solvent with a volume ratio of 1:1-1:5 as an eluent, separating through a silica gel column, and obtaining a corresponding α-boron substitution product.

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