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Fe(0)-mediated synthesis of tri- and tetra-substituted olefins from carbonyls: an environmentally friendly alternative to Cr(II).

ABSTRACT: Fe(0) was investigated as a cost-effective, environmentally friendly alternative to Cr(II) for the olefination of carbonyls by activated polyhalides. In many instances, Fe(0) was equivalent or superior to Cr(II). Notably, Fe(0), but not Cr(II), proved compatible with a wide range of functionality, inter alia, unprotected phenol, aryl nitro, carboxylic acid, and alkyl nitrile. A surprising reversal of stereoselectivity for aldehydes versus ketones was observed using both metals. The resultant alpha-halo-alpha,beta-unsaturated or alpha,beta-unsaturated carboxylic acids, esters, and nitriles are common structural elements in numerous compounds of interest as well as key intermediates in the preparation of other functionality.

SUBMITTER: Falck JR

PROVIDER: S-EPMC2516973 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Fe(0)-mediated synthesis of tri- and tetra-substituted olefins from carbonyls: an environmentally friendly alternative to Cr(II).

Falck J R JR Bejot Romain R Barma Deb K DK Bandyopadhyay Anish A Joseph Suju S Mioskowski Charles C

The Journal of organic chemistry 20061001 21

Fe(0) was investigated as a cost-effective, environmentally friendly alternative to Cr(II) for the olefination of carbonyls by activated polyhalides. In many instances, Fe(0) was equivalent or superior to Cr(II). Notably, Fe(0), but not Cr(II), proved compatible with a wide range of functionality, inter alia, unprotected phenol, aryl nitro, carboxylic acid, and alkyl nitrile. A surprising reversal of stereoselectivity for aldehydes versus ketones was observed using both metals. The resultant alp ...[more]

PMID: 17025309

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