Regioselective Carbosilylation of Allenes by Supported Au Catalysts
Hiroki Miura1,2,3, Kaede Ameyama1, Yushi Sato1
1Department of Applied Chemistry for Environment, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan.
Abstract:
This manuscript reports the development of supported Au nanoparticle catalysts that promote the regioselective carbosilylation of allenes. Single-electron transfer catalysis of Au nanoparticles enabled the generation of silyl and alkyl radicals from disilanes and redox-active esters, respectively. These radicals were selectively delivered to the β- and γ-positions of the carbonyl group in allenoates, affording the corresponding vinylsilanes. Notably, alkyl acetates could also serve as alkylating agents in the Au-catalyzed carbosilylation, providing access to a broad range of multifunctionalized vinylsilanes. Detailed mechanistic studies revealed that the reaction involves the generation of silyl radicals and alkyl radicals, which enabled this unprecedented regioselectivity. In addition, the high reusability and air tolerance of the supported Au catalysts highlight their potential for practical and sustainable synthetic applications.
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