Modular syntheses of chiral and achiral C,N-chelated Pd(II)-pyridinylidenes

Modular, high-yielding routes to achiral and chiral, C,N-chelated pyridinylidene complexes of Pd(II) have been developed which rely on oxidative addition of either chloropyridinium imines or aldehydes to Pd(0), respectively, and, in the latter case, subsequent Schiff base formation with chiral primary amines. These protocols succinctly circumvent many of the problems currently associated with the synthesis of chelating pyridinylidenes.