Reduction of a diruthenium bridging vinylidene species Cp 2Ru 2( μ-C = CH 2)(CO)( μ-CO)(MeCN) by hydrosilane leading to a vinyl complex Cp 2Ru 2( μ-CH = CH 2)(CO) 2(SiR 3) and vinylsilane: a model system for production of an olefinic product from a vinylidene intermediate

Abstract

Treatment of the labile diruthenium bridging vinylidene species, Cp 2Ru 2( μ-C = CH 2)( μ-CO)(CO)(MeCN) ( 7), with hydrosilane produces the silylated bridging vinyl complex, Cp 2Ru 2( μ- η 1: η 2-CH=CH 2)(SiR 3(CO) 2 ( 8), from which vinylsilane CH 2 = CHSiR 3 ( 19) is eliminated upon further treatment with 2e-donors. The reaction sequence, where hydrosilane works as a pseudohydrogen, can be viewed as a model system for production of an olefinic product from a vinylidene species on a heterogeneous catalyst surface. A similar reaction of 7 with HSnPh 3 gives small amounts of ethylene and Cp 2Ru 2(μ-H) 2(SnPh 3) 2(CO) 2 ( 20). The molecular structure of the SiMe 2Ph derivative of 8 has been determined by X-ray crystallography.