Formal Asymmetric Organocatalytic 3+2 Cyclization between Enecarbamates and 3-Indolylmethanols: Rapid Access to 3-Aminocyclopentabindoles

摘要

A highly enantio- and diastereoselective synthesis of 3-aminocyclopentabindoles has been developed through formal 3+2 cycloaddition reaction of enecarbamates and 3-indolylmethanols. This transformation is catalyzed by a chiral phosphoric acid that achieves simultaneous activation of both partners of the cycloaddition. Mechanistic data are also presented that suggest that the reaction occurs through a stepwise pathway.