New aspects of platinum-catalyzed hydrosilylation of disilylethynes II. Effects of oxygen and temperature

Article abstract of DOI:10.1016/0022-328X(90)85471-A

It has been found that oxygen can markedly influence the outcome of the products from platinum-catalyzed reaction of Me3SiC<*>CSiMe3 with n-C6H13Me2SiH or n-BuMe2SiOSiMe2H.Under dry air at 130 deg C, bis(trimethylsilyl)ethyne and hexyldimethylsilane apparently underwent silyl group exchange reactions to give trimethylsilane, hydrosilylation being a minor reaction.Products derived from oxidation reactions of SiH groups were also detected.With n-BuMe2SiOSiMeH hydrosilylation was a major reaction.With both hydrides, higher yields of normal adducts were obtained under nitrogen at 130 deg C than under dry air, though significant amounts of disilylethynes and isomers of the adducts were still produced.Under nitrogen at low temperature (90 deg C), the normal cis adducts were obtained in high yield, and these were isolated.Their structures were confirmed by selectively decopuled 29Si NMR.