Hydrosilylation of alkynylsilanes utilizing organolanthanide and Group 3 metallocene complexes

The organolanthanide- and Group 3 metallocene-catalyzed hydrosilylation of alkynylsilanes has been found to provide (Z)-1,1-bis(silyl)alkenes. In particular, Cp-2*YMeTHF (1), [(Cp2YMe)-Y-TMS](2) (2), and [(Cp2LuMe)-Lu-TMS](2) (3) were shown to be regioselective for the hydrosilylation of various alkynylsilanes (Fig. 1). The process was evaluated for diverse substitution patterns and functional groups on the pendant alkyl chain. Silyl ethers and halogens are stable to the catalytic process, affording excellent chemo- and regioselectivities. Competition between 'aryl-directed' and 'silyl-directed' processes was observed upon hydrosilylation of (phenylethynyl)dimethylsilane. (C) 2002 Published by Elsevier Science B.V.