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Direct and enantioselective {alpha}-allylation of ketones via singly occupied molecular orbital (SOMO) catalysis.

ABSTRACT: The first enantioselective organocatalytic ?-allylation of cyclic ketones has been accomplished via singly occupied molecular orbital catalysis. Geometrically constrained radical cations, forged from the one-electron oxidation of transiently generated enamines, readily undergo allylic alkylation with a variety of commercially available allyl silanes. A reasonable latitude in both the ketone and allyl silane components is readily accommodated in this new transformation. Moreover, three new oxidatively stable imidazolidinone catalysts have been developed that allow cyclic ketones to successfully participate in this transformation. The new catalyst platform has also been exploited in the first catalytic enantioselective ?-enolation and ?-carbooxidation of ketones.

SUBMITTER: Mastracchio A

PROVIDER: S-EPMC2996445 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Direct and enantioselective {alpha}-allylation of ketones via singly occupied molecular orbital (SOMO) catalysis.

Mastracchio Anthony A Warkentin Alexander A AA Walji Abbas M AM MacMillan David W C DW

Proceedings of the National Academy of Sciences of the United States of America 20101004 48

The first enantioselective organocatalytic α-allylation of cyclic ketones has been accomplished via singly occupied molecular orbital catalysis. Geometrically constrained radical cations, forged from the one-electron oxidation of transiently generated enamines, readily undergo allylic alkylation with a variety of commercially available allyl silanes. A reasonable latitude in both the ketone and allyl silane components is readily accommodated in this new transformation. Moreover, three new oxidat ...[more]

PMID: 20921367

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