Fig. 1: Prior arts and our work in the catalytic asymmetric reactions with 2-azaallyl anions.

a Regioselectivity in the nucleophilic addition of 2-azaallyl anions. b Reported catalytic asymmetric α-addition by Hou and Wu. c Reported catalytic asymmetric α′-addition (umpolung addition) by Deng. d Our work: synthesis of 1,2-diamines through copper(I)-catalyzed α-addition.