A Diastereodivergent and Enantioselective Approach to syn - and anti -Diamines: Development of 2-Azatrienes for Cu-Catalyzed Reductive Couplings with Imines That Furnish Allylic Amines

We introduce a new reagent class, 2-azatrienes, as a platform for catalytic enantioselective synthesis of allylic amines. Herein, we demonstrate their promise by a diastereodivergent synthesis of syn - and anti -1,2-diamines through their Cu–bis(phosphine)-catalyzed reductive couplings with imines. With Ph-BPE as the supporting ligand, anti -diamines are obtained (up to 91% yield, >20:1 dr, and >99:1 er), and with the rarely utilized t -Bu-BDPP, syn -diamines are generated (up to 76% yield, 1:>20 dr, and 97:3 er).