Structure determination of the cobalt(III) complex catalyst for enantioselective borohydride reduction

The structure of the reactie cobalt complex catalyst for the enantioselective borohydride reduction of ketones was completely determined by ESI-MS, NMR, and X-ray analyses. It was confirmed that as an axial ligand, 1-chlorovinyl group derived from 1, 1, 1-trichloroethane was attached. Based on the X-ray analysis, two rotamers on cobaltcarbon bond were found in one unit. The obtained 1-chlorovinylcobalt(III) complex was examined for the enantioselective reduction to afford the reduced product in high yield with a high enantioselectivity.