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Bifunctional catalyst promotes highly enantioselective bromolactonizations to generate stereogenic C-Br bonds.

ABSTRACT: A novel bifunctional catalyst derived from BINOL has been developed that promotes the highly enantioselective bromolactonizations of a number of structurally distinct unsaturated acids. Like some known catalysts, this catalyst promotes highly enantioselective bromolactonizations of 4- and 5-aryl-4-pentenoic acids, but it also catalyzes the highly enantioselective bromolactonizations of 5-alkyl-4(Z)-pentenoic acids. These reactions represent the first catalytic bromolactonizations of alkyl-substituted olefinic acids that proceed via 5-exo mode cyclizations to give lactones in which new carbon-bromine bonds are formed at a stereogenic center with high enantioselectivity. We also disclose the first catalytic desymmetrization of a prochiral dienoic acid by enantioselective bromolactonization.

SUBMITTER: Paull DH

PROVIDER: S-EPMC3397382 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Bifunctional catalyst promotes highly enantioselective bromolactonizations to generate stereogenic C-Br bonds.

Paull Daniel H DH Fang Chao C Donald James R JR Pansick Andrew D AD Martin Stephen F SF

Journal of the American Chemical Society 20120627 27

A novel bifunctional catalyst derived from BINOL has been developed that promotes the highly enantioselective bromolactonizations of a number of structurally distinct unsaturated acids. Like some known catalysts, this catalyst promotes highly enantioselective bromolactonizations of 4- and 5-aryl-4-pentenoic acids, but it also catalyzes the highly enantioselective bromolactonizations of 5-alkyl-4(Z)-pentenoic acids. These reactions represent the first catalytic bromolactonizations of alkyl-substi ...[more]

PMID: 22726214

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