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Construction of the tricyclic A-B-C core of the Veratrum alkaloids.

ABSTRACT: Organocatalyzed enantioselective allylation of 2-iodocyclohexenone followed by methylation and oxy-Cope rearrangement delivered enantiomerically enriched 2-methyl 3-allyl cyclohexanone, which engaged in acid-catalyzed Robinson annulation to give the bicyclic enone. Subsequent elaboration of the pendant allyl group into an ?-diazo ?-keto ester set the stage for Rh-mediated cyclization to deliver the tricyclic A-B-C core of the Veratrum alkaloids.

SUBMITTER: Taber DF

PROVIDER: S-EPMC4255024 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Construction of the tricyclic A-B-C core of the Veratrum alkaloids.

Taber Douglass F DF Berry James F JF

The Journal of organic chemistry 20130806 17

Organocatalyzed enantioselective allylation of 2-iodocyclohexenone followed by methylation and oxy-Cope rearrangement delivered enantiomerically enriched 2-methyl 3-allyl cyclohexanone, which engaged in acid-catalyzed Robinson annulation to give the bicyclic enone. Subsequent elaboration of the pendant allyl group into an α-diazo β-keto ester set the stage for Rh-mediated cyclization to deliver the tricyclic A-B-C core of the Veratrum alkaloids. ...[more]

PMID: 23859604

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