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Lewis acid-promoted Friedel-Crafts alkylation reactions with alpha-ketophosphate electrophiles.

ABSTRACT: The BF(3).OEt(2)-promoted nucleophilic substitution of alpha-aryl-alpha-ketophosphates to afford alpha,alpha-diaryl ketone products is described. Electron-rich alpha-ketophosphates perform best, with electron-neutral and electron-poor substrates also tolerated. The reaction is tolerant of a range of aromatic, heteroaromatic, and nonaromatic nucleophiles, with yields ranging from 44% to 84%. Enantioenriched starting material yields racemic product, suggesting an S(N)1 pathway via an acylcarbenium ion.

SUBMITTER: Smith AG

PROVIDER: S-EPMC2852482 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Lewis acid-promoted Friedel-Crafts alkylation reactions with alpha-ketophosphate electrophiles.

Smith Austin G AG Johnson Jeffrey S JS

Organic letters 20100401 8

The BF(3).OEt(2)-promoted nucleophilic substitution of alpha-aryl-alpha-ketophosphates to afford alpha,alpha-diaryl ketone products is described. Electron-rich alpha-ketophosphates perform best, with electron-neutral and electron-poor substrates also tolerated. The reaction is tolerant of a range of aromatic, heteroaromatic, and nonaromatic nucleophiles, with yields ranging from 44% to 84%. Enantioenriched starting material yields racemic product, suggesting an S(N)1 pathway via an acylcarbenium ...[more]

PMID: 20235527

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