Catalytic Asymmetric Construction of β-Azido Amides and Esters via Haloazidation.

A catalytic regio- and enantioselective haloazidation reaction with a chiral iron(II) complex catalyst under mild reaction conditions was reported. By this approach, the stereoselective α-halo-β-azido difunctionalization of both α,β-unsaturated amides and α,β-unsaturated esters was achieved. This method enabled the construction of a broad spectrum of valuable functionalized amides and esters, including enantiomerically enriched β-azido amides, aziridine amides, α-amino amide derivatives, β-triazole amides, functionalized peptide derivatives, and α-halo-β-azido-substituted esters.