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Enhanced anti-diastereo- and enantioselectivity in alcohol-mediated carbonyl crotylation using an isolable single component iridium catalyst.

ABSTRACT: The cyclometalated iridium complex (S)-I derived from [Ir(cod)Cl](2), 4-cyano-3-nitrobenzoic acid, allyl acetate, and (S)-SEGPHOS is conveniently isolated by precipitation or through conventional silica gel flash chromatography. This single-component precatalyst allows alcohol mediated carbonyl crotylations to be performed at significantly lower temperature, resulting in enhanced levels of anti-diastereo- and enantioselectivity. Most significantly, the chromatographically isolated precatalyst (S)-I enables carbonyl crotylations that are not possible under previously reported conditions involving in situ generation of (S)-I.

SUBMITTER: Gao X

PROVIDER: S-EPMC3064714 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Enhanced anti-diastereo- and enantioselectivity in alcohol-mediated carbonyl crotylation using an isolable single component iridium catalyst.

Gao Xin X Townsend Ian A IA Krische Michael J MJ

The Journal of organic chemistry 20110304 7

The cyclometalated iridium complex (S)-I derived from [Ir(cod)Cl](2), 4-cyano-3-nitrobenzoic acid, allyl acetate, and (S)-SEGPHOS is conveniently isolated by precipitation or through conventional silica gel flash chromatography. This single-component precatalyst allows alcohol mediated carbonyl crotylations to be performed at significantly lower temperature, resulting in enhanced levels of anti-diastereo- and enantioselectivity. Most significantly, the chromatographically isolated precatalyst (S ...[more]

PMID: 21375283

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