title: Asymmetric vinylogous Diels-Alder reactions catalyzed by a chiral phosphoric acid.
abstract: An unprecedented way to extend the synthetic utility of the Diels-Alder reaction to include a vinylogous reactivity space is described. A commercially available chiral phosphoric acid catalyst effectively activates cyclic 2,4-dienones towards a vinylogous [4+2] cycloaddition with 2-vinylindoles, which leads to stereochemically dense tetrahydrocarbazoles. The reaction proceeds with a high level of remote stereocontrol and exclusive chemoselectivity for the more distant double bond of the dienone.
authors: ICIQ-Institute of Chemical Research of Catalonia, Avenida Països Catalans 16, 43007 Tarragona (Spain) http://www.iciq.es/portal/862/default.aspx.
authors: Xu
authors: X
authors: Tian
authors: Nora
authors: N
authors: Hofmann
authors: Paolo
authors: P
authors: Melchiorre
keywords: Brønsted acids; Diels-Alder reactions; asymmetric catalysis; organocatalysis; synthetic methods