Tris(dimethylamino)sulfonium Difluorotrimethylsilicate, a Mild Reagent for the Removal of Silicon Protecting Groups

Abstract

Numerous methods have been developed for the introduction and selective removal of silicon-containing protecting groups, which are used extensively in organic synthesis.2-4 Nevertheless, there remains a great need for the development of ever milder and more selective methods for silyl group deprotection for use with baseand/or acid-sensitive substrates. Herein, we report the use of TAS-F [tris(dimethylamino)sulfonium difluorotrimethylsilicate, (Me2N)3S+ F2SiMe3] for the deprotection of a range of silyl ethers and 2-(trimethylsilyl)ethyl carbamates and esters. Particularly striking are the TAS-F-mediated deprotections of the base-sensitive substrates 1, 3, 5, 11, and 13, which could not be deprotected cleanly or efficiently by using tetra-nbutylammonium fluoride (TBAF).