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Oxonitriles: a grignard addition-acylation route to enamides.

ABSTRACT: [reaction: see text] Sequential addition of three different Grignard reagents and pivaloyl chloride to 3-oxo-1-cyclohexene-1-carbonitrile installs four new bonds to generate a diverse array of cyclic enamides. Remarkably, formation of the C-magnesiated nitrile intermediate is followed by preferential acylation by pivaloyl chloride rather than consumption by an in situ Grignard reagent. Rapid N-acylation of the C-magnesiated nitrile generates an acyl ketenimine that reacts readily with Grignard reagents or a trialkylzincate, effectively assembling highly substituted, cyclic enamides.

SUBMITTER: Fleming FF

PROVIDER: S-EPMC2518779 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Oxonitriles: a grignard addition-acylation route to enamides.

Fleming Fraser F FF Wei Guoqing G Zhang Zhiyu Z Steward Omar W OW

Organic letters 20061001 21

[reaction: see text] Sequential addition of three different Grignard reagents and pivaloyl chloride to 3-oxo-1-cyclohexene-1-carbonitrile installs four new bonds to generate a diverse array of cyclic enamides. Remarkably, formation of the C-magnesiated nitrile intermediate is followed by preferential acylation by pivaloyl chloride rather than consumption by an in situ Grignard reagent. Rapid N-acylation of the C-magnesiated nitrile generates an acyl ketenimine that reacts readily with Grignard r ...[more]

PMID: 17020332

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