Method for preparing silanol through silane hydrolysis

Abstract

The invention provides a method for preparing silanol by silane hydrolysis, which comprises the following steps of: reacting silane serving as a reaction raw material, water serving as an oxide and a metal compound serving as a catalyst to obtain silanol; wherein the molecular formula of the silane is SiHR1R2R3, and R1, R2 and R3 are independently selected from C1-C4 alkyl, phenyl, alkyl-substituted phenyl, halogen-substituted phenyl and alkoxy-substituted phenyl; the metal compound is carbonate of sodium, potassium or cesium. According to the method for preparing silanol through silane hydrolysis, hydrogen is a unique by-product and cannot pollute the environment, and the requirement for green catalysis is met. In addition, the metal compound catalyst is low in cost, the target product silanol can be separated by extracting a reaction mixture, the product yield is high, operation is simple, and implementation is easy. In addition, the method is mild in reaction condition and easy for industrial application.

Description

Technical Field

[0001] This invention belongs to the field of organic compound preparation technology, specifically relating to a method for preparing silanols by hydrolysis of silanes. Background Technology

[0002] Silanols are structural analogs of alcohols and are a very important and valuable class of compounds. In materials chemistry, silanols can be used as building blocks for the synthesis of silicon-based polymer materials; in medicinal chemistry, silanols can be used as bioisosteres of alcohols; in organic synthesis methodology, silanols can be used as coupling reagents, CH activation directing agents, and small organic molecule catalysts.

[0003] Currently, there are three main methods for synthesizing silanols: The first is to prepare silanols through the hydrolysis of chlorosilanes. This method has excellent reactivity, but HCl is generated during the hydrolysis of chlorosilanes, and the silanols generated under acidic conditions are prone to self-condensation reactions to form silyl ethers. The second method is to oxidize hydrosilanes using an equivalent amount of strong oxidant. Currently, strong oxidants that can oxidize hydrosilanes include silver salts, permanganates, osmium tetroxide, peroxyacids, and ozone. However, the use of strong oxidants has disadvantages such as a narrow substrate range and poor reaction selectivity, and it also generates an equivalent amount of waste. Using transition metal catalysts to catalyze hydrosilanes is currently the most commonly used method by researchers, but some problems still exist, such as the high cost of transition metals and their difficulty in preparation.

[0004] Chinese patent CN 103923114 B discloses a relatively common and inexpensive copper salt as a catalyst, water as an oxidant, and hydrogen gas as a byproduct of the catalytic process, which has high atom economy.

[0005] Chinese patent CN 115448942 A discloses a method using [N(C4H9)4]4[Mo8O] 26 This invention discloses a method for preparing silanols using a catalyst, achieving high yields with a catalyst dosage of only 0.5 mol%. The invention employs a novel catalyst for silanol preparation, utilizes a one-step process, and uses commercially available raw materials. Furthermore, the catalyst exhibits excellent stability and is easily stored.

[0006] However, existing transition metal catalysts still suffer from high costs, with most catalysts being difficult to purchase directly and their synthesis proving challenging, thus hindering the large-scale production of silanols. Therefore, further research is needed in this field on catalysts for silane hydrolysis. Summary of the Invention

[0007] The main objective of this invention is to provide a method for preparing silanols by hydrolysis of silanes, so as to overcome the defects of existing technologies such as high cost of catalysts and difficulty in synthesis for silane hydrolysis.

[0008] To achieve the above objectives, the present invention provides a method for preparing silanol by hydrolysis of silane, wherein silane is used as a reactant, water is used as an oxide, and a metal compound is used as a catalyst to carry out the reaction and obtain silanol;

[0009] The silane has the molecular formula SiHR1R2R3, where R1, R2, and R3 are independently selected from C1-C4 alkyl, phenyl, alkyl-substituted phenyl, halogen-substituted phenyl, and alkoxy-substituted phenyl.

[0010] The metal compound is a carbonate of sodium, potassium, or cesium.

[0011] The method for preparing silanol by hydrolysis of silane according to the present invention, wherein the number of alkyl substituents in the alkyl-substituted phenyl group is one or two, and the alkyl substituent has one to four carbons.

[0012] The method for preparing silanol by hydrolysis of silane according to the present invention, wherein the number of halogen substituents in the halogen-substituted phenyl group is one or two, and the halogen substituent is fluorine or chlorine.

[0013] The method for preparing silanol by hydrolysis of silane according to the present invention, wherein the number of alkoxy substituents in the alkoxy-substituted phenyl group is one or two, and the alkoxy substituent has one to four carbons.

[0014] The method for preparing silanol by hydrolysis of silane according to the present invention, wherein the sodium, potassium or cesium carbonate includes sodium carbonate, potassium carbonate and cesium carbonate.

[0015] The method for preparing silanol by hydrolysis of silane according to the present invention includes the addition of an organic solvent to the reaction, the reaction temperature being 30-80°C, and the reaction time being 6-18 hours.

[0016] The method for preparing silanol by hydrolysis of silane according to the present invention, wherein the organic solvent includes at least one selected from dichloromethane, n-hexane, tetrahydrofuran, acetonitrile, ethyl acetate, tert-butanol, and dimethylformamide.

[0017] The method for preparing silanol by hydrolysis of silane according to the present invention, wherein the molar ratio of catalyst to silane is 0.01-0.2:1; and the molar ratio of water to silane is 1-10:1.

[0018] The method for preparing silanol by hydrolysis of silane according to the present invention includes obtaining a reaction mixture by means of extraction, solvent removal, and column chromatography separation of the reaction mixture to obtain the silanol.

[0019] The beneficial effects of this invention are:

[0020] This invention uses silane as a raw material, water as an oxidant, and a metal compound as a catalyst to prepare silanol. Hydrogen is the only byproduct, causing no environmental pollution and meeting the requirements of green catalysis. Furthermore, the metal compound catalyst of this invention is low-cost, and the target product, silanol, can be separated by extraction of the reaction mixture, resulting in high product yield and simple, easy-to-implement operation. Moreover, the reaction conditions of this invention are mild, facilitating industrial application. Attached Figure Description

[0021] Figure 1 The 1H NMR spectrum of triethylsilanol in Example 1 ( 1 H NMR).

[0022] Figure 2 The 1H NMR spectrum of triisopropylsilanol in Example 2 ( 1 H NMR).

[0023] Figure 3 The 1H NMR spectrum of methyldiphenylsilanol in Example 3 ( 1 H NMR).

[0024] Figure 4 The 1H NMR spectrum of triphenylsilanol in Example 4 ( 1 H NMR).

[0025] Figure 5 The 1H NMR spectrum of dimethyl(p-chloro)phenylsilanol in Example 5 ( 1 H NMR).

[0026] Figure 6 The 1H NMR spectrum of dimethyl(p-fluoro)phenylsilanol in Example 6 ( 1 H NMR).

[0027] Figure 7 The 1H NMR spectrum of dimethyl(p-ethyl)phenylsilanol in Example 7 ( 1 H NMR).

[0028] Figure 8 The 1H NMR spectrum of dimethyl(3,5-dimethyl)phenylsilanol in Example 8 ( 1 HNMR).

[0029] Figure 9 The 1H NMR spectrum of dimethyl(o-methoxy)phenylsilanol in Example 9 ( 1 HNMR). Detailed Implementation

[0030] The technical solution of the present invention will be described in detail below. The following embodiments are implemented under the premise of the technical solution of the present invention and a detailed implementation process is given. However, the protection scope of the present invention is not limited to the following embodiments. Structures or experimental methods that do not specify specific conditions in the following embodiments are generally performed under conventional conditions.

[0031] The main objective of this invention is to provide a method for preparing silanol by hydrolysis of silane, using silane as the reactant, water as the oxide, and a metal compound as the catalyst to carry out the reaction and obtain silanol;

[0032] The silane has the molecular formula SiHR1R2R3, where R1, R2, and R3 are independently selected from C1-C4 alkyl, phenyl, alkyl-substituted phenyl, halogen-substituted phenyl, and alkoxy-substituted phenyl.

[0033] The metal compound is a carbonate of sodium, potassium, or cesium.

[0034] This invention uses silane as a raw material, water as an oxidant, and a metal compound as a catalyst to prepare silanol. Hydrogen is the only byproduct, causing no environmental pollution and meeting the requirements of green catalysis. Furthermore, the metal compound catalyst of this invention is low-cost, and the target product, silanol, can be separated by extraction of the reaction mixture, resulting in high product yield and simple, easy-to-implement operation. Moreover, the reaction conditions of this invention are mild, facilitating industrial application.

[0035] The silane of this invention has the molecular formula SiHR1R2R3, where R1, R2, and R3 are independently selected from C1-C4 alkyl, phenyl, alkyl-substituted phenyl, halogen-substituted phenyl, and alkoxy-substituted phenyl. R1, R2, and R3 may be the same or different.

[0036] In one embodiment, the C1-C4 alkyl group is, for example, methyl, ethyl, n-propylene, isopropylene, n-butyl, isobutyl, neobutyl, etc. In another embodiment, the alkyl-substituted phenyl group has one or two alkyl substituents, each having one to four carbons, and is, for example, methyl, ethyl, n-propylene, isopropylene, n-butyl, isobutyl, neobutyl, etc. The present invention does not particularly limit the substitution position of the alkyl substituents, for example, ortho, meta, para, etc. In yet another embodiment, the halogen-substituted phenyl group has one or two halogen substituents, and the halogen substituents can be fluorine or chlorine. The present invention does not particularly limit the substitution position of the halogen substituents, for example, ortho, meta, para, etc. In yet another embodiment, the alkoxy-substituted phenyl group has one or two alkoxy substituents, each having one to four carbons, for example, methoxy, ethoxy, propoxy, butoxy, etc. The present invention does not specifically limit the substitution position of the alkoxy substituent, such as ortho, meta, para, etc.

[0037] In one specific embodiment, the silane of the present invention includes one of the following: triethylsilane, triisopropylsilane, dimethylphenylsilane, methyldiphenylsilane, triphenylsilane, dimethyl(p-methoxy)phenylsilane, dimethyl(p-chloro)phenylsilane, dimethyl(p-fluoro)phenylsilane, dimethyl(p-ethyl)phenylsilane, dimethyl(3,5-dimethyl)phenylsilane, and dimethyl(o-methoxy)phenylsilane.

[0038] The catalyst of this invention is a metal compound, specifically a carbonate of sodium, potassium, or cesium. The sodium, potassium, or cesium carbonate is sodium carbonate, potassium carbonate, or cesium carbonate.

[0039] In one embodiment, the molar ratio of silane to water in this invention is 1:1-10, for example, 1:2-10, 1:3-10, 1:4-10, 1:5-10, 1:6-10, 1:7-10, etc. The molar ratio of catalyst to silane is 0.2-0.01:1, for example, 0.05-0.2:1, 0.1-0.2:1, 0.12-0.2:1, 0.15-0.2:1.

[0040] Specifically, under the same conditions, cesium carbonate exhibits higher catalytic activity compared to sodium carbonate and potassium carbonate. When the catalyst is potassium carbonate or sodium carbonate, the preferred molar ratio of the catalyst to silane is greater than or equal to 0.1:1, more preferably greater than or equal to 0.2:1, and even more preferably 0.2-1.0:1.

[0041] In one embodiment, an organic solvent, such as at least one selected from dichloromethane, n-hexane, tetrahydrofuran, acetonitrile, ethyl acetate, tert-butanol, and dimethylformamide, is also added to the reaction. The reaction temperature is 30-80°C, and the reaction time is 6-18 hours.

[0042] In one embodiment, the method for preparing silanol by hydrolysis of silane according to the present invention includes the following steps: mixing silane, water, an organic solvent, and a catalyst, reacting at 30-80°C in an air atmosphere for 6-18 hours, and obtaining a reaction mixture after the reaction is complete. The reaction mixture is then extracted, the solvent is removed, and separated by column chromatography to obtain the silanol. In another embodiment, the reaction temperature is 60°C, the reaction time is 12 hours, the extraction solvent is, for example, ethyl acetate and dichloromethane / or water, and the solvent is removed by, for example, drying.

[0043] The silanols obtained by the method of this invention exhibit good stability and good tolerance to functional groups. This method generates only hydrogen as a byproduct, and the post-processing of the reaction mixture is simple. The catalysts are widely available and require small amounts, thus solving the problems of high toxicity, high cost, and poor selectivity associated with transition metals.

[0044] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0045] Raw material source:

[0046]

[0047] Some of the raw materials were prepared in-house using existing technology. The specific preparation process is as follows:

[0048]

[0049] Under N2 protection at 0 °C, Grignard reagent (10 mL, 1.0 M in THF) was slowly added dropwise to a THF solution of dimethylchlorosilane (0.89 mL, 8 mmol) or diphenylchlorosilane (1.57 mL, 8 mmol) (6 mL). The reaction was stirred at room temperature for 4 h. The remaining Grignard reagent was quenched with saturated NH4Cl solution and extracted with Et2O (15 mL × 3). Diethyl ether was removed under reduced pressure, and the residue was purified by silica gel column chromatography (with n-hexane as eluent) to obtain the corresponding silane substrate.

[0050] Example 1

[0051] 0.23 g (2 mmol) of triethylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried (to remove water) and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated by silica gel (200-300 mesh) column chromatography to obtain 0.251 g of pure triethylsilanol (yield 97%).

[0052] The obtained triethylsilanol was characterized by nuclear magnetic resonance. Figure 1 The NMR spectrum of the obtained triethylsilanol, 1 H NMR (400MHz, CDCl3) δ1.98 (s, 1H), 0.94 (t, J = 7.9Hz, 9H), 0.56 (q, J = 8.2Hz, 6H).

[0053] Example 2

[0054] 0.32 g (2 mmol) of triisopropylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum distillation to obtain the crude product. Finally, the crude product was separated by silica gel (200-300 mesh) column chromatography to obtain 0.292 g of pure triisopropylsilanol (yield 89%).

[0055] The obtained triisopropylsilanol was characterized by NMR. Figure 2 The NMR spectrum of the obtained triisopropylsilanol is shown. 1 HNMR (400MHz, CDCl3) δ1.73 (s, 1H), 1.03 (s, 21H).

[0056] Example 3

[0057] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.376 g of pure methyldiphenylsilanol (yield 88%).

[0058] The obtained methyldiphenylsilanol was characterized by nuclear magnetic resonance. Figure 3 The NMR spectrum of the obtained methyldiphenylsilanol is shown. 1 H NMR (400MHz, CDCl3) δ7.64–7.62(m,4H),7.45–7.40(m,6H),2.05(s,1H),0.67(s,3H).

[0059] Example 4

[0060] 0.26 g (1 mmol) of triphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.09 mL (5 mmol) of H2O, and 3 mg (0.01 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. Then, 15 mL of ethyl acetate was added for extraction three times. The mixture was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.228 g of pure triphenylsilanol (yield 83%).

[0061] The obtained triphenylsilanol was characterized by nuclear magnetic resonance. Figure 4 The NMR spectrum of the obtained triphenylsilanol is shown. 1 H NMR (400MHz, CDCl3) δ7.45 (d, J = 7.5Hz, 6H), 7.33 (t, J = 7.4Hz, 3H), 7.16 (t, J = 7.5Hz, 6H), 1.54 (s, 1H).

[0062] Example 5

[0063] 0.34 g (2 mmol) of dimethyl(p-chloro)phenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.350 g of pure dimethyl(p-chloro)phenylsilanol (yield 94%).

[0064] The obtained dimethyl(p-chloro)phenylsilanol was characterized by nuclear magnetic resonance. Figure 5 The NMR spectrum of the obtained dimethyl(p-chloro)phenylsilanol is shown below. 1 H NMR (400MHz, CDCl3) δ7.44 (d, J = 8.2 Hz, 2H), 7.33 (d, J = 8.2 Hz, 2H), 1.27 (s, 1H), 0.33 (s, 6H).

[0065] Example 6

[0066] 0.31 g (2 mmol) of dimethyl(p-fluoro)phenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum distillation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.312 g of pure dimethyl(p-fluoro)phenylsilane (yield 92%).

[0067] The obtained dimethyl(p-fluoro)phenylsilanol was characterized by nuclear magnetic resonance. Figure 6 The NMR spectrum of the obtained dimethyl(p-fluoro)phenylsilanol is shown below. 1H NMR (400MHz, CDCl3) δ7.55–7.30(m,2H),7.04–6.85(m,2H),2.21(s,1H),0.23(s,6H).

[0068] Example 7

[0069] 0.33 g (2 mmol) of dimethyl(p-ethyl)phenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. Then, 15 mL of ethyl acetate was added for extraction three times. The mixture was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.290 g of pure dimethyl(p-ethyl)phenylsilane (yield 81%).

[0070] The obtained dimethyl(p-ethyl)phenylsilanol was characterized by nuclear magnetic resonance. Figure 7 The NMR spectrum of the obtained dimethyl (p-ethyl)phenylsilanol is shown. 1 H NMR (400MHz, CDCl3) δ7.53 (d, J = 8.0Hz, 2H), 7.31–7.20 (m, 2H), 2.76–2.56 (m, 2H), 2.03 (s, 1H), 1.26 (t, J = 7.6Hz, 3H), 0.40 (s, 6H).

[0071] Example 8

[0072] 0.33 g (2 mmol) of dimethyl(3,5-dimethyl)phenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. Then, 15 mL of ethyl acetate was added for extraction three times. The mixture was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.298 g of pure dimethyl(3,5-dimethyl)phenylsilanol (yield 83%).

[0073] The obtained dimethyl(3,5-dimethyl)phenylsilanol was characterized by nuclear magnetic resonance. Figure 8 The NMR spectrum of the obtained dimethyl(3,5-dimethyl)phenylsilanol is shown below. 1 H NMR (400MHz, CDCl3) δ7.23 (s, 2H), 7.07 (s, 1H), 2.35 (s, 6H), 1.29 (d, J = 2.3Hz, 1H), 0.41 (s, 6H).

[0074] Example 9

[0075] 0.33 g (2 mmol) of dimethyl(o-methoxy)phenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. Then, 15 mL of ethyl acetate was added for extraction three times. The mixture was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.253 g of pure dimethyl(o-methoxy)phenylsilane (yield 76%).

[0076] The obtained dimethyl(o-methoxy)phenylsilanol was characterized by nuclear magnetic resonance. Figure 9 The NMR spectrum of the obtained dimethyl(o-methoxy)phenylsilanol is shown below. 1 H NMR: (400MHz, CDCl3): δ7.46 (dd, J=7.1, 1.7Hz, 1H), 7.40 (td, J=7.9, 1.8Hz, 1H), 7 .01(t,J=7.3Hz,1H),6.88(d,J=8.3Hz,1H),3.84(s,3H),2.77(s,1H),0.42(s,6H).

[0077] Example 10

[0078] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 13.7 mg (0.1 mmol) of potassium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel column (200-300 mesh) to obtain 0.152 g of pure methyldiphenylsilanol (yield 35%).

[0079] Example 11

[0080] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 55 mg (0.4 mmol) of potassium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.325 g of pure methyldiphenylsilanol (yield 76%).

[0081] Example 12

[0082] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 8.4 mg (0.1 mmol) of sodium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.158 g of pure methyldiphenylsilanol (yield 37%).

[0083] Example 13

[0084] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 42 mg (0.4 mmol) of sodium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.337 g of pure methyldiphenylsilanol (yield 79%).

[0085] Example 14

[0086] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.11 mL (6.11 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was then quenched with an aqueous solution, followed by extraction three times with 15 mL of ethyl acetate. The mixture was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.334 g of pure methyldiphenylsilanol (yield 78%).

[0087] Example 15

[0088] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.36 mL (20 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.377 g of pure methyldiphenylsilanol (yield 88%).

[0089] Example 16

[0090] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 8 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.240 g of pure methyldiphenylsilanol (yield 56%).

[0091] Example 17

[0092] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 80 °C for 12 h until the reaction was complete. The reaction was then quenched with an aqueous solution, followed by extraction three times with 15 mL of ethyl acetate. The mixture was dried and the solvent was removed by vacuum distillation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.308 g of pure methyldiphenylsilanol (yield 72%).

[0093] Example 18

[0094] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (20 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 16 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum distillation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.347 g of pure methyldiphenylsilanol (yield 81%).

[0095] Example 19

[0096] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of tert-butanol, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was then quenched with an aqueous solution, followed by extraction three times with 15 mL of ethyl acetate. The mixture was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.197 g of pure methyldiphenylsilane (yield 46%).

[0097] Example 20

[0098] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of dimethylformamide, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 60 °C for 24 h until the reaction was complete. The reaction was quenched with an aqueous solution, and then extracted three times with 15 mL of ethyl acetate. The product was dried and the solvent was removed by vacuum evaporation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.270 g of pure methyldiphenylsilanol (yield 63%).

[0099] Example 21

[0100] 0.40 g (2 mmol) of methyldiphenylsilane was added to a 100 mL dry round-bottom flask, followed by 3 mL of acetonitrile, 0.18 mL (10 mmol) of H2O, and 6 mg (0.02 mmol) of cesium carbonate catalyst. The mixture was stirred at 40 °C for 24 h until the reaction was complete. The reaction was then quenched with an aqueous solution, followed by extraction three times with 15 mL of dichloromethane. The mixture was dried and the solvent was removed by vacuum distillation to obtain the crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column to obtain 0.378 g of pure methyldiphenylsilanol (yield 88%).

[0101] Comparative Example 1

[0102] Under a nitrogen atmosphere, 0.372 g (20 mol%) of 6,6'-diaminobipyridine and 0.361 g (10 mol%) of Mn(ClO4)2 were added to a dried round-bottom flask in 3 mL of acetone solution. The mixture was stirred at 75 °C for 0.5 h to obtain a manganese complex as a catalyst. Then, 0.2 g (1 mmol) of methyldiphenylsilane was added, and H2O (5 mmol, 90 μL) was added over 15 minutes via syringe at room temperature. After reacting for 60 minutes, the mixture was quenched with a saturated Na2SO3 aqueous solution. The mixture was then extracted three times with 15 mL of ethyl acetate, dried, and the solvent was removed under reduced pressure to obtain a crude product. Finally, the crude product was separated using a silica gel (200-300 mesh) column, but the target product was not obtained.

[0103] In Comparative Example 1, a manganese complex was used as a catalyst. When water was added as an oxidant, the catalyst's catalytic effect was very poor, and it was even difficult to obtain the target product.

[0104] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing silanol by hydrolysis of silane, characterized in that, Using silane as a reactant, water as an oxide, and a metal compound as a catalyst, a reaction is carried out to obtain silanol; The silane has the molecular formula SiHR1R2R3, where R1, R2, and R3 are independently selected from C1-C4 alkyl, phenyl, alkyl-substituted phenyl, halogen-substituted phenyl, and alkoxy-substituted phenyl. The metal compound is a carbonate of sodium, potassium, or cesium.

2. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The alkyl-substituted phenyl group has one or two alkyl substituents, and the alkyl substituents have one to four carbons.

3. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The halogen-substituted phenyl group has one or two halogen substituents, and the halogen substituents are fluorine or chlorine.

4. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The alkoxy-substituted phenyl group has one or two alkoxy substituents, and the alkoxy substituents have 1 to 4 carbons.

5. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The sodium, potassium, or cesium carbonates include sodium carbonate, potassium carbonate, and cesium carbonate.

6. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The reaction also involved the addition of an organic solvent, and the reaction temperature was 30-80°C, with a reaction time of 6-18 hours.

7. The method for preparing silanol by hydrolysis of silane according to claim 6, characterized in that, The organic solvent includes at least one of dichloromethane, n-hexane, tetrahydrofuran, acetonitrile, ethyl acetate, tert-butanol, and dimethylformamide.

8. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The molar ratio of water to silane is 1-10:

1.

9. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The molar ratio of the catalyst to silane is 0.01-0.2:

1.

10. The method for preparing silanol by hydrolysis of silane according to claim 1, characterized in that, The reaction yields a reaction mixture, which is then extracted, solvent removed, and separated by column chromatography to obtain the silanol.

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