Salt‐Free Preparation of Trimethylsilyl Ethers by B(C₆F₅)₃‐Catalyzed Transfer Silylation by Using a Me₃SiH Surrogate

Abstract

An unprecedented transfer silylation of alcohols catalyzed by the strong Lewis acid B(C6F5)3 is described. Gaseous Me3SiH is released in situ by B(C6F5)3‐catalyzed decomposition of 3‐trimethylsilylcyclohexa‐1,4‐diene and subsequently reacts with an alcohol in a dehydrogenative Si–O coupling promoted by the same boron catalyst. Benzene and dihydrogen are formed during the reaction, but no salt waste is. This expedient protocol is applicable to several silicon groups, and the preparation of trimethylsilyl ethers presented here is potentially useful for alcohol derivatization prior to GLC analysis.

Silylation of Alcohols, Phenols, and Silanols with Alkynylsilanes – an Efficient Route to Silyl Ethers and Unsymmetrical Siloxanes

“…[6][7][8][9][10] to their most known function as a temporary protective group for hydroxyl moieties (e.g., natural products synthesis, derivatization, etc.). [11][12][13][14] There are several methods of their synthesis, starting with classical condensation between alcohols and halosilanes, [15] and finishing on catalytic coupling reactions with hydro-, [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] vinyl- [33] or allylsilanes, [34,35] and more recently also with silyl formates. [36][37][38] However, in the case of O-silylation of alcohols with alkynylsilanes -this process has never been comprehensively studied, and previous investigations have mainly referred to the problem of C sp -Si bond stability rather than the application of this transformation as an efficient method for obtaining silyl ethers.…”

Silylation of O–H bonds by catalytic dehydrogenative and decarboxylative coupling of alcohols with silyl formates

“…3). 10 Recently, we demonstrated that silylformates, HCO2SiR3, could serve as a new class of hydrosilane surrogates in the transfer hydrosilylation of aldehydes, by formal decarboxylation of the formate ligand in the presence of a metal catalyst. 11 This approach has the advantage of utilizing formic acid, a mild reductant derived from biomass or CO2, as a hydride source.…”

Catalytic Formation of Silicon–Heteroatom (N, P, O, S) Bonds

“…It is thus always a major drawback if hydrosilanes are involved in the catalysis, because a trace amount of water or even a small amount of oxygen can be a source of disiloxane oxygen . Finally, the Oestreich group report unprecedented dehydrocoupling between in situ generated trimethylsilane and alcohols mediated by B(C 6 F 5 ) 3 (Scheme ) . 3‐Silylated cyclohexa‐1,4‐dienes serve as excellent trimethylsilane surrogates.…”