Ruthenium-Catalyzed Hydrosilylation of Aldehydes with Hydrooligosilanes

Ruthenium-catalyzed hydrosilylation of aldehydes with hydrooligosilanes is reported. Among the examined ruthenium catalysts, RuH2(CO)(PPh3)3 gave the best results. The reactions proceed with the Si-Si bonds preserved to afford the corresponding alkoxyoligosilanes in good yields. A series of aryl aldehydes with an electron-withdrawing group is applicable, whereas those with an electron-donating group are not suitable for the reaction. Mechanistic considerations suggest that the key points for the preservation of the Si-Si bonds are the formation of zero-valent ruthenium species and the efficient coordination of the aldehyde to the ruthenium center prior to the oxidative addition of the Si-H bond. image