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Stereoselective C-glycosidations with achiral and enantioenriched allenylsilanes.

ABSTRACT: Allenylsilanes are used as carbon nucleophiles in highly stereoselective Lewis acid-promoted C-glycosidations, resulting in the introduction of an internal alkyne with an adjacent stereocenter. Both achiral and chiral allenylsilanes form the desired products with high diastereoselectivity, where the nucleophile adds exclusively to the ?-face of the intermediate oxonium ion. Reactions with glucal and galactal afford dihydropyran products, while reactions with a ribose derivative yield dihydrofuran products.

SUBMITTER: Brawn RA

PROVIDER: S-EPMC3156056 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Stereoselective C-glycosidations with achiral and enantioenriched allenylsilanes.

Brawn Ryan A RA Panek James S JS

Organic letters 20101001 20

Allenylsilanes are used as carbon nucleophiles in highly stereoselective Lewis acid-promoted C-glycosidations, resulting in the introduction of an internal alkyne with an adjacent stereocenter. Both achiral and chiral allenylsilanes form the desired products with high diastereoselectivity, where the nucleophile adds exclusively to the α-face of the intermediate oxonium ion. Reactions with glucal and galactal afford dihydropyran products, while reactions with a ribose derivative yield dihydrofura ...[more]

PMID: 20839812

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