Hydrosilylation of Allenes Over Palladium-Gold Alloy Catalysts: Enhancing Activity and Switching Selectivity by the Incorporation of Palladium into Gold Nanoparticles
route to alkenylsilnaes involving hydrosilylation of allenes by supported palladium-gold alloy catalysts has been developed. The catalytic activity and the product selectivity were drastically changed by the incorporation of palladium atoms into goldnanoparticles (NPs). The supported Pd-Au alloy catalysts with a low Pd/Au ratio were highly effective for the hydrosilylation at ambient temperature, in which
Palladiumnanoparticles stabilized with tris‐imidazolium tetrafluoroborates catalyze the stereoselective hydrosilylation of internalalkynes in a dry inert atmosphere to give (E)‐vinylsilanes in excellent yields. In the presence of controlled amounts of water a transfer hydrogenation reaction takes place with the formation of (Z)‐alkenes or the corresponding alkanes.
Ligandless Regioselective Hydrosilylation of Allenes Catalyzed by Gold Nanoparticles
作者:Marios Kidonakis、Manolis Stratakis
DOI:10.1021/acs.orglett.5b02236
日期:2015.9.18
The first example of Au-catalyzed hydrosilylation of allenes is presented using recyclable gold nanoparticles as catalyst, without the requirement of any external ligands or additives. The hydrosilane addition takes place on the more substituted double bond of terminal allenes in a highly regioselective manner. The observed regioselectivity/reactivity modes are attributed to steric and electronic factors.