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.

SUBMITTER: Ji K 

PROVIDER: S-EPMC3817591 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature