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Enantioselective polyene cyclization via organo-SOMO catalysis.

ABSTRACT: The first organocatalytic enantioselective radical polycyclization has been accomplished using singly occupied molecular orbital (SOMO) catalysis. The presented strategy relies on a selective single-electron oxidation of chiral enamines formed by condensation of polyenals with an imidazolidinone catalyst employing a suitable copper(II) oxidant. The reaction proceeds under mildly acidic conditions at room temperature and shows compatibility with an array of electron-poor as well as electron-rich functional groups. Upon termination by radical arylation followed by subsequent oxidation and rearomatization, a range of polycyclic aldehydes were accessed (12 examples, 54-77% yield, 85-93% ee). The enantioselective formation of up to six new carbocycles in a single catalyst-controlled cascade is described. Evidence for a radical-based cascade mechanism is indicated by a series of experimental results.

SUBMITTER: Rendler S

PROVIDER: S-EPMC2880463 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Enantioselective polyene cyclization via organo-SOMO catalysis.

Rendler Sebastian S Macmillan David W C DW

Journal of the American Chemical Society 20100401 14

The first organocatalytic enantioselective radical polycyclization has been accomplished using singly occupied molecular orbital (SOMO) catalysis. The presented strategy relies on a selective single-electron oxidation of chiral enamines formed by condensation of polyenals with an imidazolidinone catalyst employing a suitable copper(II) oxidant. The reaction proceeds under mildly acidic conditions at room temperature and shows compatibility with an array of electron-poor as well as electron-rich ...[more]

PMID: 20334384

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