title: Bimolecular Coupling Reactions through Oxidatively Generated Aromatic Cations: Scope and Stereocontrol.
abstract: Chromenes, isochromenes, and benzoxathioles react with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone to form stable aromatic cations that react with a range of nucleophiles. These oxidative fragment coupling reactions provide rapid access to structurally diverse heterocycles. Conducting the reactions in the presence of a chiral Brønsted acid results in the formation of an asymmetric ion pair that can provide enantiomerically enriched products in a rare example of a stereoselective process resulting from the generation of a chiral electrophile through oxidative carbon-hydrogen bond cleavage.
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, Telephone: (+1)412-62408727.
authors.forename: Yubo
authors.initials: Y
authors.lastname: Cui
authors.forename: Louis A
authors.initials: LA
authors.lastname: Villafane
authors.forename: Dane J
authors.initials: DJ
authors.lastname: Clausen
authors.forename: Paul E
authors.initials: PE
authors.lastname: Floreancig
keywords: chiral counterions; enantioselectivity; fragment coupling; heterocycles; oxidation
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