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Gold-catalyzed regioselective oxidation of propargylic carboxylates: a reliable access to ?-carboxy-?,?-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. ?-Carboxy ?,?-unsaturated ketones/aldehydes can be obtained with fair to excellent yields.

SUBMITTER: Ji K

PROVIDER: S-EPMC3817591 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Gold-catalyzed regioselective oxidation of propargylic carboxylates: a reliable access to α-carboxy-α,β-unsaturated ketones/aldehydes.

Ji Kegong K Nelson Jonathan J Zhang Liming L

Beilstein journal of organic chemistry 20130924

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 formatio ...[more]

PMID: 24204402

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