Optically active diphosphine, transition metal complex containing the same, and process for producing optically active compound using the complex

摘要

Disclosed are an optically active diphosphine represented by formula: <IMAGE> wherein R represents a lower alkyl group having 1 to 4 carbon atoms; Ar represents a phenyl group which may be substituted with a lower alkyl group having 1 to 4 carbon atoms and/or a lower alkoxy group having 1 to 4 carbon atoms, a transition metal complex containing the diphosphine as a ligand, and a process for producing an optically active delta -oxo- alpha -cyano ester using the transition metal complex as a catalyst.