Umpolung Synthesis of Vicinal Diamines: Diastereoselective Addition of 2‑Azaallyl Anions to Davis–Ellman’s Imines

A highly regioselective and diastereoselective addition of 2-azaallyl anions to N-tert-butanesulfinylimines is reported. This methodology affords the preparation of enantiomerically and diastereomerically pure vicinal diamines bearing two adjacent stereocenters. Reactions proceed efficiently (yield up to 94%), diastereoselectively (dr values up to 98:2:0:0), and site-selectively to deliver products with differentiated amino groups.