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Polyol synthesis with beta-oxyanionic alkyllithium reagents: syntheses of aculeatins A, B, and D.

ABSTRACT: Synthesis of ketone aldol products using a non-aldol route was developed. The beta-phenylthio alcohols were prepared from optically pure oxiranes. Deprotonation and reductive lithiation generated the key intermediate, a beta-oxyanionic alkyllithium reagent. Addition to a Weinreb amide produced the beta-hydroxy ketone in >90% yield using only 1.5 equiv of the phenylthio alcohol. Stereoselective reduction of the ketone led to either the syn- or anti-1,3-diol. This simple, convergent sequence was used to prepare aculeatins A, B, and D from a common intermediate.

SUBMITTER: Malathong V

PROVIDER: S-EPMC2741543 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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Polyol synthesis with beta-oxyanionic alkyllithium reagents: syntheses of aculeatins A, B, and D.

Malathong Viengkham V Rychnovsky Scott D SD

Organic letters 20090901 18

Synthesis of ketone aldol products using a non-aldol route was developed. The beta-phenylthio alcohols were prepared from optically pure oxiranes. Deprotonation and reductive lithiation generated the key intermediate, a beta-oxyanionic alkyllithium reagent. Addition to a Weinreb amide produced the beta-hydroxy ketone in >90% yield using only 1.5 equiv of the phenylthio alcohol. Stereoselective reduction of the ketone led to either the syn- or anti-1,3-diol. This simple, convergent sequence was u ...[more]

PMID: 19691310

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