METATHESIS OF SILICON-CONTAINING OLEFINS .5. CROSS-METATHESIS OF VINYLTRIETHOXYSILANE WITH OLEFINS CATALYZED BY RUTHENIUM COMPLEXES

Synthetic and catalytic studies on cross-metathesis of vinyltriethoxysilane with 1-alkenes, 2-alkenes, branched alkenes, cycloalkenes, styrene, vinylcyclohexene and vinyltrimethylsilane and some functionalized alkenes catalyzed by RuCl3.nH2O and RuCl2(PPh3)3 are presented. Some of the efficient reactions examined can be applied as novel methods for the synthesis of new silicon-containing olefins or new synthetic approaches to well known olefins. A preliminary kinetic and stoichiometric study also aims to elucidate the mechanism of cross-metathesis and its conditions for synthetic application. The catalytic cycle for cross-metathesis occurs competitively with that for self-metathesis of vinylsilane. The formation of complexes of ruthenium relatively strongly bonded with olefins, e.g. Ru-styrene complex, plays a decisive role in the effective cross-metathesis.