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Enantioselective organo-SOMO cascade cycloadditions: a rapid approach to molecular complexity from simple aldehydes and olefins.

ABSTRACT: A highly selective, radical-mediated (4 + 2) coupling reaction of aldehydes and conjugated olefins has been achieved through asymmetric SOMO-catalysis. A radical-polar crossover mechanism is proposed wherein olefin addition to a transient enamine radical cation and oxidation of the resulting radical furnishes a cation which is vulnerable to nucleophilic addition. A range of aromatic aldehydes are shown to couple with styrenes and dienes to provide cyclic products with high chemical efficiency, regioselectivity, and stereoselectivity.

SUBMITTER: Jui NT

PROVIDER: S-EPMC3041020 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Enantioselective organo-SOMO cascade cycloadditions: a rapid approach to molecular complexity from simple aldehydes and olefins.

Jui Nathan T NT Lee Esther C Y EC MacMillan David W C DW

Journal of the American Chemical Society 20100701 29

A highly selective, radical-mediated (4 + 2) coupling reaction of aldehydes and conjugated olefins has been achieved through asymmetric SOMO-catalysis. A radical-polar crossover mechanism is proposed wherein olefin addition to a transient enamine radical cation and oxidation of the resulting radical furnishes a cation which is vulnerable to nucleophilic addition. A range of aromatic aldehydes are shown to couple with styrenes and dienes to provide cyclic products with high chemical efficiency, r ...[more]

PMID: 20593858

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