Deoxygenative Silylation of C(sp<sup>3</sup>)–O Bonds with Hydrosilane by Cooperative Catalysis of Gold Nanoparticles and Solid Acids
Hiroki Miura, Yuki Yasui, Yosuke Masaki, Masafumi Doi, Tetsuya Shishido
Abstract
Efficient deoxygenative silylation of C(sp 3 )–O bonds with hydrosilanes by supported Au catalysts is described. Gold nanoparticles supported on TiO 2 enabled various hydrosilanes to be used as sources of silyl groups in C–Si cross-coupling reactions. A variety of alkyl acetates and propargyl carbonates participated in the Au-catalyzed reactions to furnish the corresponding alkyl and allenylsilanes in high yields. In addition, Au/TiO 2 was also effective for ring-opening silylation of cyclic ethers. A detailed mechanistic investigation corroborated that the title reaction involves the formation of silyl and alkyl radical intermediates, and the cooperation of Au nanoparticles as single-electron transfer catalysts and Lewis acid sites at the surface of metal oxides was responsible for the unusual reactivity of hydrosilanes for specific C(sp 3 )–Si bond formation.