Novel Catalytic Hydrogenolysis of Trimethylsilyl Enol Ethers by the Use of an Acidic Ruthenium Dihydrogen Complex.

Abstract

The heterolytic cleavage of H(2) is the key to the novel catalytic hydrogenolysis of trimethylsilyl enol ethers catalyzed by [RuCl(eta(2)-H(2))(dppe)(2)]OTf (dppe = 1,2-bis(diphenylphosphanyl)ethane, OTf = trifluoromethanesulfonate), which results in the formation of a ketone and Me(3)SiH (see scheme). In addition, the stoichiometric, ruthenium-assisted protonation of a prochiral lithium enolate with H(2) gave a chiral ketone with high enantioselectivity (up to 75 % ee).