title: Gold-catalyzed regioselective oxidation of propargylic carboxylates: a reliable access to α-carboxy-α,β-unsaturated ketones/aldehydes.
abstract: Gold-catalyzed intermolecular oxidation of carboxylates of primary or secondary propargylic alcohols are realized with excellent regioselectivity, which is ascribed to inductive polarization of the C-C triple bond by the electron-withdrawing carboxy group. The gold carbene intermediates thus generated undergo selective 1,2-acyloxy migration over a 1,2-C-H insertion, and the selectivities could be dramatically improved by the use of a P,S-bidentate ligand, which is proposed to enable the formation of tris-coordinated and hence less electrophilic gold carbene species. α-Carboxy α,β-unsaturated ketones/aldehydes can be obtained with fair to excellent yields.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, 93106, USA.
authors.forename: Kegong
authors.initials: K
authors.lastname: Ji
authors.forename: Jonathan
authors.initials: J
authors.lastname: Nelson
authors.forename: Liming
authors.initials: L
authors.lastname: Zhang
keywords: enone; gold catalysis; oxidation; propargyl carboxylate