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A reductive cyclization approach to attenol A.

ABSTRACT: A reductive cyclization strategy was applied to the synthesis of attenol A. This nontraditional approach to the spiroacetal structure illustrated several advantages of the reductive cyclization methodology. The attenol A core was formed in a carbon-carbon bond coupling that gave rise to a previously inaccessible spiroacetal epimer, a new method to synthesize thioketene acetals from a phenyl sulfone was realized, and the configurational stability of a nonanomeric spiroacetal was evaluated. A minor byproduct in the reductive cyclization reaction was identified that for the first time allowed direct evaluation of the stereoselectivity in a reductive cyclization of a dialkyloxy alkyllithium reagent.

SUBMITTER: La Cruz TE

PROVIDER: S-EPMC2504508 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature

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A reductive cyclization approach to attenol A.

La Cruz Thomas E TE Rychnovsky Scott D SD

The Journal of organic chemistry 20070309 7

A reductive cyclization strategy was applied to the synthesis of attenol A. This nontraditional approach to the spiroacetal structure illustrated several advantages of the reductive cyclization methodology. The attenol A core was formed in a carbon-carbon bond coupling that gave rise to a previously inaccessible spiroacetal epimer, a new method to synthesize thioketene acetals from a phenyl sulfone was realized, and the configurational stability of a nonanomeric spiroacetal was evaluated. A mino ...[more]

PMID: 17346087

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