a, Nickel-catalyzed addition of organozinc halides to styrenyl aziridines (22) occurs with incorporation of the nucleophile (23) at the substituted position of the aziridine to furnish β,β-disubstituted amines (24). b, Nickel-catalyzed addition of organozinc halides (23) to aliphatic aziridines (25) directed by the cinsyl group, which imparts a preference for addition at the less substituted position of the aziridine. Ts, (4-methyl)phenylsulfonyl; DME, 1,2-dimethoxyethane; DMA, dimethylacetamide.