Box-copper catalyzed cascade asymmetric amidation for chiral exo-methylene aminoindoline derivatives

Org Biomol Chem. 2021 Nov 10;19(43):9373-9378. doi: 10.1039/d1ob01242h.

Abstract

Enantioselective copper-catalyzed cascade inter- and intramolecular amidation was achieved between ethynyl benzoxazinanones and α-halohydroxamates in the presence of an indapybox ligand. The one-pot cascade transformation was triggered by the attack of hydroxamates to dipolar copper-allenylidene intermediates, followed by a nucleophilic annulation reaction. Thus, a series of exo-methylene 3-aminoindoline derivatives were obtained in good yields with high enantioselectivities under mild reaction conditions.