Chiral α-amino phosphonates via rhodium-catalyzed asymmetric 1,4-addition reactions.

A new approach for the preparation of enantioenriched α-amino phosphonates and derivatives is described. Indeed, the rhodium-catalyzed asymmetric 1,4-addition of potassium organotrifluoroborates to dehydroaminophosphonates afforded α-amino phosphonates in good yields and high enantioselectivities (up to 96%) using Difluorphos as a chiral ligand.