Bench-Stable Manganese NHC Complexes for the Selective Reduction of Esters to Alcohols with Silanes

Selective reduction of esters to alcohols was accomplished through Mn(I)-mediated hydrosilylation reaction. The manganese tricarbonyl complex [Mn(bis-NHC)(CO)(3)Br] resulted an active pre-catalyst for the reduction of a variety of esters using phenylsilane and the cheap and readily available polymethylhydrosiloxane. Anin situexamination of the catalytic reaction using(55)Mn NMR spectroscopy allowed us to detect the formation of Mn(I) intermediate active species.