A formally zwitterionic ruthenium catalyst precursor for the transfer hydrogenation of ketones that does not feature an ancillary ligand N-H dunctionality

Abstract

Fast and furious: Even without the assistance of an N-H donor ligand, the Ra complex shown in the scheme is a remarkably active precatalyst for the transfer hydrogenation of ketones in basic iPrOH (R,R′ = alkyl oraryl), providing near-quantitative yields within minutes and exhibiting consistently high turnover frequencies (104 to 105 h-1) for a diverse range of substrates. (Chemical Equation Presented). © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.