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Continuum of mechanisms for nucleophilic substitutions of cyclic acetals.

ABSTRACT: The effect of nucleophile strength on diastereoselectivity in the nucleophilic substitution of cyclic acetals was explored. Stereoselectivity remained constant and high as nucleophilicity increased until a threshold value was reached. Beyond this point, however, selection of Lewis acid determined whether stereochemical inversion or erosion was observed.

SUBMITTER: Krumper JR

PROVIDER: S-EPMC2664297 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Continuum of mechanisms for nucleophilic substitutions of cyclic acetals.

Krumper Jennifer R JR Salamant Walter A WA Woerpel K A KA

Organic letters 20081010 21

The effect of nucleophile strength on diastereoselectivity in the nucleophilic substitution of cyclic acetals was explored. Stereoselectivity remained constant and high as nucleophilicity increased until a threshold value was reached. Beyond this point, however, selection of Lewis acid determined whether stereochemical inversion or erosion was observed. ...[more]

PMID: 18844363

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