First P*,P-bidentate ligand with a chiral bicyclic phosphoramidite framework

Abstract

The first P*,P-bidentate ligand of the 2,6-dioxa-7-aza-1-phosphabicyclo[2.2.1]heptane series possessing a rigid P-chiral phosphoramidite framework and an additional phosphine donor center in a side substituent was synthesized. A cis-bis-chelate complex containing two molecules of a phosphino dialkyl phosphite derivative of this ligand was obtained. The use of the new P*,P-ligand as a chiral inducer in Pd-catalyzed asymmetric allylic alkylation of (E)-1,3-diphenylallyl acetate with dimethyl malonate and cinnamyl acetate with ethyl 2-oxocyclohexane-1-carboxylate provided ee of up to 46% and 53%, respectively.