Asymmetric N-alkylation of indoles with isatins catalyzed by N-heterocyclic carbene: efficient synthesis of functionalized cyclic N,O-aminal indole derivatives†
Abstract
An N-heterocyclic carbene-catalyzed enantioselective N-alkylation of indole-2-formaldehydes with isatins has been achieved. Functionalized cyclic N,O-aminal indole derivatives were obtained in good yields with excellent enantioselectivities.