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Gold(I)-catalyzed enantioselective synthesis of benzopyrans via rearrangement of allylic oxonium intermediates.

ABSTRACT: The first transition metal catalyzed asymmetric carboalkoxylation reaction of propargyl esters is described. The (R)-MeO-DTBM-BIPHEP(AuCl)(2)-catalyzed reactions allow for the construction of benzopyrans containing quaternary stereocenters with excellent enantioselectivity. Experimental evidence supports a mechanism proceeding via the generation of a stabilized carbocation from an allylic oxonium intermediate and subsequent trapping by a chiral allylgold(I) spieces.

SUBMITTER: Uemura M

PROVIDER: S-EPMC2664525 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Gold(I)-catalyzed enantioselective synthesis of benzopyrans via rearrangement of allylic oxonium intermediates.

Uemura Minoru M Watson Iain D G ID Katsukawa Mikimoto M Toste F Dean FD

Journal of the American Chemical Society 20090301 10

The first transition metal catalyzed asymmetric carboalkoxylation reaction of propargyl esters is described. The (R)-MeO-DTBM-BIPHEP(AuCl)(2)-catalyzed reactions allow for the construction of benzopyrans containing quaternary stereocenters with excellent enantioselectivity. Experimental evidence supports a mechanism proceeding via the generation of a stabilized carbocation from an allylic oxonium intermediate and subsequent trapping by a chiral allylgold(I) spieces. ...[more]

PMID: 19236093

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