{Reference Type}: Journal Article
{Title}: Exploiting the Multidentate Nature of Chiral Disulfonimides in a Multicomponent Reaction for the Asymmetric Synthesis of Pyrrolo[1,2-a]indoles: A Remarkable Case of Enantioinversion.
{Author}: Galván A;González-Pérez AB;Álvarez R;de Lera AR;Fañanás FJ;Rodríguez F;
{Journal}: Angew Chem Int Ed Engl
{Volume}: 55
{Issue}: 10
{Year}: Mar 2016 1
{Factor}: 16.823
{DOI}: 10.1002/anie.201511231
{Abstract}: A new multicomponent coupling reaction for the enantioselective synthesis of pyrrolo[1,2-a]indoles under the catalysis of a chiral disulfonimide is described. The high specificity of the reaction is a consequence of the multidentate character of the Brønsted acid catalyst. Insights from DFT calculations helped explain the unexpected high enantioselectivity observed with the simplest 3,3'-unsubstituted binaphthyl catalyst as a result of transition-state stabilization by a network of cooperative noncovalent interactions. The remarkable enantioinversion resulting from the simple introduction of substituents at 3- and 3'-positions, the first reported example of this phenomenon in the context of binaphthalene-derived Brønsted acid catalysis, was instead attributed to destabilizing steric interactions.