METATHESIS OF SILICON-CONTAINING OLEFINS .11. METATHESIS OF VINYLSUBSTITUTED SILANES IN THE PRESENCE OF RUTHENIUM COMPLEXES

Novel synthetic application of the versatile reaction, the metathesis of vinyltrisubstituted silanes and their co-metathesis with alkenes, d ienes and allylsilanes, has been reported. Metathesis of vinyltrimethy lsilane is efficiently catalyzed by many ruthenium complexes yielding E-bis(silyl)ethene and, unexpectedly 1,1-bis(silyl)ethene (only in the presence of phenylphosphine ligand at ruthenium) as main products acc ompanied by products of dimerization and co-dimerization. A sequence o f five pathways initiating two essential mechanisms - by metal carbene species and the insertion of vinylsilane into Ru-Si (Ru-H) and beta-H (beta-Si) elimination of products was proposed.