Organic electrochemical synthesis method of silyl ether

Abstract

The invention relates to an organic electrochemical synthesis method of silyl ether, in particular to a transition-metal-free synthesis method, which comprises the following steps: adding cyclobutyl silane, methanol, an additive, electrolyte and a solvent into a reaction flask under anhydrous and anaerobic conditions, electrifying at normal temperature, and stirring for 1.0 hour; according to the present invention, the use of noble metals is mainly avoided, and new organic conversion is developed by using electrons as the redox reagent under the mild condition, such that the stoichiometric oxidizing agent or reducing agent is avoided, and the unnecessary waste is reduced so as to meet the increasing requirements of environmental friendliness and sustainability. The method is simple and easy to operate, the materials required in the method are low in toxicity, safe and environment-friendly, the substrate expansion range is wide, and the yield is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic compound synthesis, and relates to a method for electrochemically mediated ring-opening synthesis of silyl ethers from cyclobutylsilanes. Background Art

[0002] As an important structural unit, silyl ethers have extensive application values in the fields of medicine, agrochemistry, and materials science, and are key intermediates in many organic transformation applications. Therefore, the efficient and facile synthesis of organic silyl ethers is an important research direction in silicon chemistry. In traditional synthesis methods, the cleavage of cyclobutylsilanes to form silyl ethers mainly relies on Lewis acid catalysts (such as boron trifluoride, aluminum trichloride, etc.) or transition metal catalysis (such as metal complexes of palladium, rhodium, platinum, nickel, etc.). However, these methods have obvious limitations: the Lewis acid system often produces corrosive hydrochloric acid by-products, causing environmental pollution; while transition metal catalysts are relatively expensive and scarce in storage. With the in-depth development of the concept of green chemistry, the development of an environmentally friendly method for synthesizing silyl ethers has become the current research focus. Based on this, we propose a new method for the organic electrochemical synthesis of silyl ethers. Electrochemical synthesis has mild reaction conditions, high selectivity, and can optimize and precisely control the reaction process by adjusting parameters such as current density and electrode potential. This method not only avoids the environmental pollution problems of traditional methods but also greatly improves the controllability and repeatability of the reaction, providing a new idea for the green synthesis of silyl ethers.

[0003] [(a) A.K. Franz, P.D. Dreyfuss, S.L. Schreiber, J. Am. Chem. Soc., 2007, 129, 1020 - 1021. (b) W. Yuan, L. You, W. Lin, J. Ke, Y. Li, C. He, Org. Lett., 2021, 23, 1367 - 1372. (c) X. Quan, L. Xu, Z. Li, P. Maienfisch, J. Agric. Food Chem., 2023, 71, 18188 - 18196. (d) W.-K. Zhu, H.-J. Zhu, X.-J. Fang, F. Ye, J. Cao, Z. Xu, L.-W. Xu, Org. Lett., 2023, 25, 7186 - 7191. (e) S. Liu, Y.-S. Chen, Y. Wu, P. Wang, Sci. Chi. Chem., 2024, 67, 2661 - 2669. (f) J.J. Dalton, A. Bernal Sánchez, A.T. Kelly, J.C. Fettinger, A.K. Franz, ACS Catal., 2024, 14, 1005 - 1012.] Summary of the Invention

[0004] The purpose of this section is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this section, the abstract, and the title. However, such simplifications or omissions shall not be used to limit the scope of the present invention.

[0005] (1) Technical Problem

[0006] The present invention mainly avoids the use of precious metals, stoichiometric oxidants or reductants, and solves the problem of generating unnecessary waste to meet the growing requirements for environmental friendliness and sustainability.

[0007] (2) Technical Solution

[0008] The reaction flask is equipped with a graphite felt and a platinum sheet electrode. The graphite felt serves as the anode and the platinum sheet serves as the cathode. Under nitrogen protection, 0.2 mmol of cyclobutylsilane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultra-dry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile are successively added to the reaction flask, and stirred at room temperature for 1.0 h with a current of 8 mA.

[0009] The above-mentioned cyclobutylsilane is one of 1,1-diphenylsilacyclobutane, 1,1-di-p-tolylsilacyclobutane, 1,1-bis(thiophen-2-yl)silacyclobutane, 1,1-bis(4-methoxyphenyl)silacyclobutane, 1,1-bis(4-chlorophenyl)silacyclobutane, 1-(4-methoxyphenyl)-1-methylsilacyclobutane, 1-(4-tert-butylphenyl)-1-methylsilacyclobutane, 1-methyl-1-(4-methylthiophenyl)silacyclobutane, 1-benzyl-1-methylsilacyclobutane, 7-phenyl-7-methyl-7-silabicyclo[4.2.0]octa-1,3,5-triene; the methanol is ultra-dry methanol; the additive is triethylamine; the electrode materials are graphite felt and platinum sheet electrode; the electrolyte is tetrabutylammonium tetrafluoroborate; the solvent is acetonitrile.

[0010] The molar ratio of the additive to cyclobutylsilane is 1:2; the amount of methanol used is 0.4 ml; the amount of the electrolyte used is 0.05 mol / ml; the amount of the solvent used is 4 ml.

[0011] (3) Beneficial Effects and Innovations

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present invention mainly avoids the use of precious metals, develops new organic transformations by using electrons as redox reagents under mild conditions, thereby avoiding stoichiometric oxidants or reductants, reducing unnecessary waste, and meeting the growing demands for environmental friendliness and sustainability.

[0014] The present invention is simple and easy to operate. The items required in the method have low toxicity, are safe for the environment, have a wide substrate expansion range, and high yields. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. Among them:

[0016] Figure 1 1H NMR spectrum of the product prepared in Example 1 of the present invention;

[0017] Figure 2 13C NMR spectrum of the product prepared in Example 1 of the present invention. Detailed Embodiments

[0018] To make the above objects, features, and advantages of the present invention more obvious and understandable, the detailed embodiments of the present invention will be described in detail below in conjunction with the embodiments of the specification.

[0019] Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0020] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation manner of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that excludes other embodiments.

[0021] Example 1

[0022] Electrochemically catalyze the reaction of 1,1-diphenylsilacyclobutane with ultradry methanol. The reaction process is as follows:

[0023] The reaction flask was equipped with a graphite felt and a platinum sheet electrode. The graphite felt served as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of 1,1-diphenylsilylcyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile were successively added to the reaction flask, and stirred at room temperature for 1.0 h with a current of 8 mA. After the reaction was completed, the reaction mixture was filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases were combined, and the solvent was removed using a rotary evaporator to obtain the crude product. The crude product was separated by silica gel column chromatography using petroleum ether and ethyl acetate as the eluents, and finally 45.6 mg of the product was obtained with a yield of 89%.

[0024] The product was characterized as follows: 1 H NMR (600 MHz, CDCl3): δ 7.60 (dd, J = 7.9, 1.5 Hz, 4H), 7.46 - 7.41 (m, 2H), 7.41 - 7.38 (m, 4H), 3.55 (s, 3H), 1.52 - 1.45 (m, 2H), 1.19 - 1.15 (m, 2H), 1.00 (t, J = 7.3 Hz, 3H); 13 C NMR (151 MHz, CDCl3): δ 134.9, 134.7, 129.8, 127.9, 51.4, 18.2, 16.77, 16.1; HRMS (ESI): calculated for C 16 H 21 OSi + [M + H] + : 257.1356; found: 257.1358.

[0025] The structural formula of the product is:

[0026] Example 2

[0027] The electrochemical catalysis reaction of 1,1-di(p-tolyl)silylcyclobutane and ultradry methanol was carried out as follows:

[0028] The reaction flask was equipped with a graphite felt and a platinum sheet electrode. The graphite felt served as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of 1,1-di(p-tolyl)silylcyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile were successively added to the reaction flask, and stirred at room temperature for 1.0 h with a current of 8 mA. After the reaction was completed, the reaction mixture was filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases were combined, and the solvent was removed using a rotary evaporator to obtain the crude product. The crude product was separated by silica gel column chromatography using petroleum ether and ethyl acetate as the eluents, and finally 30.1 mg of the product was obtained with a yield of 53%.

[0029] Characterize the product: 1 1H NMR (600 MHz, CDCl3): δ 7.49 (d, J = 7.8 Hz, 4H), 7.21 (d, J = 7.5 Hz, 4H), 3.52 (s, 3H), 2.37 (s, 6H), 1.49 - 1.42 (m, 2H), 1.14 - 1.11 (m, 2H), 0.98 (t, J = 7.3 Hz, 3H). 13 13C NMR (151 MHz, CDCl3): δ 139.68, 134.77, 131.43, 128.67, 51.28, 21.58, 18.21, 16.68, 16.26. HRMS (ESI): calculated for C 18 H 25 OSi + [M + H] + :: 285.1669; found: 285.1674.

[0030] The structural formula of the product is:

[0031] Example 3

[0032] Electrochemically catalyze the reaction of 1,1 - bis(thiophen - 2 - yl)silacyclobutane with ultradry methanol. The reaction process is as follows:

[0033] The reaction flask is equipped with a graphite felt and a platinum plate electrode. The graphite felt is the anode and the platinum plate is the cathode. Under nitrogen protection, 0.2 mmol of 1,1 - bis(thiophen - 2 - yl)silacyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile are successively added to the reaction flask, and stirred at room temperature with a current of 8 mA for 1.0 h. After the reaction is completed, the reaction mixture is filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases are combined, the solvent is removed using a rotary evaporator to obtain a crude product, and the crude product is separated by silica gel column chromatography using petroleum ether and ethyl acetate as eluents, and finally 39.1 mg of the product is obtained with a yield of 73%. Characterize the product: 1 1H NMR (600 MHz, CDCl3): δ 7.71 (dd, J = 4.6, 0.9 Hz, 2H), 7.45 (dd, J = 3.4, 0.9 Hz, 2H), 7.25 (dd, J = 4.6, 3.4 Hz, 2H), 3.55 (s, 3H), 1.55 - 1.50 (m, 2H), 1.18 - 1.14 (m, 2H), 1.00 (t, J = 7.3 Hz, 3H). 1313C NMR (151 MHz, CDCl3): δ 136.82, 133.63, 132.09, 128.24, 51.49, 18.28, 17.97, 16.54. HRMS (ESI): calculated for C 12 H 17 OS2Si + [M + H] + : 269.0485; found: 269.0487.

[0034] The structural formula of the product is:

[0035] Example 4

[0036] Electrochemically catalyze the reaction of 1,1-bis(4-methoxyphenyl)silacyclobutane with ultradry methanol. The reaction process is as follows:

[0037] The reaction flask is equipped with a graphite felt and a platinum plate electrode. The graphite felt is used as the anode and the platinum plate as the cathode. Under nitrogen protection, 0.2 mmol of 1,1-bis(4-methoxyphenyl)silacyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile are successively added to the reaction flask, and stirred at room temperature with a current of 8 mA for 1.0 h. After the reaction is completed, the reaction mixture is filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases are combined, and the solvent is removed using a rotary evaporator to obtain the crude product. The crude product is separated by silica gel column chromatography using petroleum ether and ethyl acetate as eluents, and finally 36.7 mg of the product is obtained with a yield of 58%.

[0038] Characterize the product: 1 1H NMR (600 MHz, CDCl3): δ 7.48 (d, J = 7.9 Hz, 4H), 7.21 (d, J = 8.1 Hz, 4H), 3.51 (s, 3H), 2.37 (s, 6H), 1.48 - 1.42 (m, 2H), 1.13 - 1.11 (m, 2H), 0.97 (t, J = 7.3 Hz, 3H). 13 13C NMR (151 MHz, CDCl3): δ 139.68, 134.77, 131.42, 128.67, 51.28, 21.57, 18.21, 16.67, 16.25. HRMS (ESI): calculated for C 18 H 25 O3Si + [M + H] + : 317.1567; found: 317.1568.

[0039] The structural formula of the product is:

[0040]

[0041] Example 5

[0042] Electrochemically catalyze the reaction of 1,1-bis(4-chlorophenyl)silacyclobutane with ultradry methanol. The reaction process is as follows:

[0043] The reaction flask is equipped with a graphite felt and a platinum plate electrode. The graphite felt is used as the anode and the platinum plate is used as the cathode. Under nitrogen protection, 0.2 mmol of 1,1-bis(4-chlorophenyl)silacyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile are successively added to the reaction flask, and stirred at room temperature with a current of 8 mA for 1.0 h. After the reaction is completed, the reaction mixture is filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases are combined, and the solvent is removed using a rotary evaporator to obtain the crude product. The crude product is separated by silica gel column chromatography, and petroleum ether and ethyl acetate are used as the eluent. Finally, 43.6 mg of the product is obtained, and the yield is 67%.

[0044] Characterize the product: 1 H NMR(600MHz, CDCl3): δ7.48(d, J = 8.2Hz, 4H), 7.37(d, J = 8.2Hz, 4H), 3.51(s, 3H), 1.45 - 1.40(m, 2H), 1.14 - 1.11(m, 2H), 0.98(t, J = 7.2Hz, 3H). 13 CNMR(151MHz, CDCl3): δ136.45, 135.93, 135.48, 132.82, 128.28, 51.34, 18.07, 16.50, 15.81. HRMS(ESI): calculated for C 16 H 19 Cl2OSi + [M + H] + : 325.0577; found: 325.0577.

[0045] The structural formula of the product is:

[0046] Example 6

[0047] Electrochemically catalyze the reaction of 1-(4-methoxyphenyl)-1-methylsilacyclobutane with ultradry methanol. The reaction process is as follows:

[0048] The reaction flask was equipped with a graphite felt and a platinum sheet electrode. The graphite felt served as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of 1-(4-methoxyphenyl)-1-methylsilylcyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile were successively added to the reaction flask, and stirred at room temperature with a current of 8 mA for 1.0 h. After the reaction was completed, the reaction mixture was filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases were combined, and the solvent was removed using a rotary evaporator to obtain the crude product. The crude product was separated by silica gel column chromatography using petroleum ether and ethyl acetate as eluents, and finally 31.8 mg of the product was obtained with a yield of 71%.

[0049] The product was characterized as follows: 1 H NMR (600 MHz, CDCl₃): δ 7.49 (d, J = 8.7 Hz, 2H), 6.93 (d, J = 8.6 Hz, 2H), 3.82 (s, 3H), 3.43 (s, 3H), 1.45 - 1.38 (m, 2H), 0.97 (t, J = 7.3 Hz, 3H), 0.89 - 0.79 (m, 2H), 0.35 (s, 3H). 13 C NMR (151 MHz, CDCl₃): δ 160.82, 135.24, 134.80, 113.60, 55.02, 50.70, 18.12, 17.48, 16.66, -4.16. HRMS (ESI): calculated for C 12 H 21 O₂Si + [M + H] + : 225.1305; found: 225.1301.

[0050] The structural formula of the product is:

[0051]

[0052] Example 7

[0053] The electrochemical catalysis reaction of 1-(4-tert-butylphenyl)-1-methylsilylcyclobutane with ultradry methanol was carried out as follows:

[0054] The reaction flask was equipped with a graphite felt and a platinum plate electrode. The graphite felt served as the anode and the platinum plate as the cathode. Under nitrogen protection, 0.2 mmol of 1-(4-tert-butylphenyl)-1-methylsilacyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile were successively added to the reaction flask, and stirred at 8 mA and room temperature for 1.0 h. After the reaction was completed, the reaction mixture was filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases were combined, and the solvent was removed using a rotary evaporator to obtain the crude product. The crude product was separated by silica gel column chromatography using petroleum ether and ethyl acetate as eluents, and finally 43.0 mg of the product was obtained with a yield of 86%.

[0055] The product was characterized as follows: 1 H NMR (600 MHz, CDCl3): δ 7.50 (d, J = 8.2 Hz, 2H), 7.41 (d, J = 8.2 Hz, 2H), 3.45 (s, 3H), 1.46 - 1.41 (m, 2H), 1.33 (s, 9H), 0.98 (t, J = 7.3 Hz, 3H), 0.89 - 0.82 (m, 2H), 0.36 (s, 3H). 13 C NMR (151 MHz, CDCl3): δ 152.52, 133.59, 124.80, 50.81, 34.70, 31.23, 18.16, 17.45, 16.67, -4.19. HRMS (ESI): calculated for C 15 H 27 OSi + [M + H] + : 251.1826; found: 251.1826.

[0056] The structural formula of the product is:

[0057] Example 8

[0058] The electrochemical catalysis reaction of 1-methyl-1-(4-methylthiophenyl)silacyclobutane with ultradry methanol was carried out as follows:

[0059] The reaction flask is equipped with a graphite felt and a platinum sheet electrode. The graphite felt serves as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of 1-methyl-1-(4-methylthiophenyl)silacyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate salt, 0.4 ml of ultra-dry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile are successively added to the reaction flask, and stirred at room temperature with a current of 8 mA for 1.0 h. After the reaction is completed, the reaction mixture is filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases are combined, and the solvent is removed using a rotary evaporator to obtain the crude product. The crude product is separated by silica gel column chromatography using petroleum ether and ethyl acetate as eluents, and finally 43.2 mg of the product is obtained with a yield of 90%.

[0060] The product was characterized as follows: 1 H NMR (600 MHz, CDCl3): δ 7.46 (d, J = 8.1 Hz, 2H), 7.26 (d, J = 8.1 Hz, 2H), 3.44 (s, 3H), 2.49 (s, 3H), 1.44 - 1.38 (m, 2H), 0.97 (t, J = 7.3 Hz, 3H), 0.89 - 0.79 (m, 2H), 0.35 (s, 3H). 13 C NMR (151 MHz, CDCl3): δ 140.46, 134.09, 132.79, 125.51, 50.77, 18.09, 17.38, 16.61, 15.21, -4.24. HRMS (ESI): calculated for C 12 H 21 OSSi + [M + H] + : 241.1077; found: 241.1077.

[0061] The structural formula of the product is:

[0062]

[0063] Example 9

[0064] The electrochemical catalysis reaction of 1-benzyl-1-methylsilacyclobutane and ultra-dry methanol is as follows:

[0065] The reaction flask was equipped with a graphite felt and a platinum sheet electrode. The graphite felt served as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of 1-benzyl-1-methylsilylcyclobutane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultra-dry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile were successively added to the reaction flask, and stirred at room temperature for 1.0 h with a current of 8 mA. After the reaction was completed, the reaction mixture was filtered through diatomaceous earth, rinsed with ethyl acetate, and the organic phases were combined. The solvent was removed using a rotary evaporator to obtain the crude product, and the crude product was separated by silica gel column chromatography using petroleum ether and ethyl acetate as the eluents, and finally 21.6 mg of the product was obtained with a yield of 52%.

[0066] The product was characterized as follows: 1 H NMR(600MHz, CDCl3): δ7.22(t, J = 7.7Hz, 2H), 7.10 - 7.05(m, 3H), 3.42(s, 3H), 2.23 - 2.13(m, 2H), 1.42 - 1.33(m, 2H), 0.95(t, J = 7.3Hz, 3H), 0.67 - 0.54(m, 2H), 0.06(s, 3H). 13 C NMR(151MHz, CDCl3): δ139.09, 128.35, 128.28, 124.16, 50.75, 25.00, 18.10, 16.70, 16.56, -4.66. HRMS(ESI): calculated for C 12 H 21 OSi + [M + H] + : 209.1356; found: 209.1356.

[0067] The structural formula of the product is:

[0068] Example 10

[0069] The reaction of electrochemically catalyzing 7-phenyl-7-methyl-7-silabicyclo[4.2.0]octa-1,3,5-triene with ultra-dry methanol was carried out as follows:

[0070] The reaction flask was equipped with a graphite felt and a platinum sheet electrode. The graphite felt served as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of 7-phenyl-7-methyl-7-sila-bicyclo[4.2.0]octa-1,3,5-triene, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultradry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile were successively added to the reaction flask, and stirred at 8 mA at room temperature for 1.0 h. After the reaction was completed, the reaction mixture was filtered through diatomaceous earth, rinsed with ethyl acetate, the organic phases were combined, and the solvent was removed using a rotary evaporator to obtain the crude product. The crude product was separated by silica gel column chromatography using petroleum ether and ethyl acetate as eluents, and finally 38.7 mg of the product was obtained with a yield of 80%.

[0071] The product was characterized as follows: 1 H NMR(600MHz,CDCl3): δ7.60 - 7.53(m, 3H), 7.44 - 7.39(m, 1H), 7.39 - 7.35(m, 2H), 7.33(td, J = 7.5, 1.5Hz, 1H), 7.24 - 7.19(m, 1H), 7.17(d, J = 7.6Hz, 1H), 3.54(s, 3H), 2.33(s, 3H), 0.68(s, 3H). 13 C NMR(151MHz,CDCl3): δ144.16, 136.39, 135.59, 134.16, 130.15, 129.96, 129.72, 127.90, 124.90, 51.02, 22.69, -2.83. HRMS(ESI): calculated for C 15 H 19 OSi + [M + H] + : 243.1200; found: 243.1199.

[0072] The structural formula of the product is:

[0073] The present invention provides an organic electrochemical synthesis method for silyl ethers.

[0074] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. Under anhydrous and oxygen-free conditions, add cyclotetrasilane, methanol, additives, electrolytes, and solvents into the reaction bottle, and stir the mixture at room temperature for 1.0 hour.

2. The molar ratio of the additive to cyclotetrasilane is 1:2; the amount of methanol used is 0.4 ml; the amount of the electrolyte used is 0.05 mol / ml; and the amount of the solvent used is 4 ml.

3. The cyclotetrasilane is one of 1,1-diphenylsilylcyclobutane, 1,1-di-p-tolylsilylcyclobutane, 1,1-di(thiophen-2-yl)silylcyclobutane, 1,1-di(4-methoxyphenyl)silylcyclobutane, 1,1-di(4-chlorophenyl)silylcyclobutane, 1-(4-methoxyphenyl)-1-methylsilylcyclobutane, 1-(4-tert-butylphenyl)-1-methylsilylcyclobutane, 1-methyl-1-(4-methylthiophenyl)silylcyclobutane, 1-benzyl-1-methylsilylcyclobutane and 7-phenyl-7-methyl-7-silylbicyclo[4.2.0]octa-1,3,5-triene; the methanol is ultra-dry methanol; the triethylamine is 0.1 mmol; the electrode materials are graphite felt and platinum sheet electrodes; the electrolyte is tetrabutylammonium tetrafluoroborate; and the solvent is acetonitrile.

4. The reaction bottle is equipped with graphite felt and platinum sheet electrodes, with the graphite felt as the anode and the platinum sheet as the cathode. Under nitrogen protection, 0.2 mmol of cyclotetrasilane, 0.2 mmol of tetrabutylammonium tetrafluoroborate, 0.4 ml of ultra-dry methanol, 0.1 mmol of triethylamine, and 4 ml of acetonitrile are added to the reaction bottle in sequence, and the current is 8 mA and stirred at room temperature for 1.0 h.

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