A highly enantio- and diastereoselective synthesis of 3-aminocyclopenta[b]indoles 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.
Keywords: asymmetric synthesis; chirality; cycloaddition; enamide; iminium; indoles.
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.