Chiral N-phosphonyl imine chemistry: asymmetric aza-Henry reaction.

A series of chiral N-phosphonyl imines have been synthesized and utilized successfully in asymmetric aza-Henry reaction. The chiral auxiliary was optimized for this reaction by varying different R groups on the nitrogen atoms. The reaction is convenient to perform to give excellent yields and good diastereoselectivities. The absolute stereochemistry was unambiguously determined by converting a resulting vicinal nitroamine into its N-Boc derivative which serves as a known compound.