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Catalyst-controlled regioselectivity in the synthesis of branched conjugated dienes via aerobic oxidative Heck reactions.

ABSTRACT: Pd-catalyzed aerobic oxidative coupling of vinylboronic acids and electronically unbiased alkyl olefins provides regioselective access to 1,3-disubstituted conjugated dienes. Catalyst-controlled regioselectivity is achieved by using 2,9-dimethylphenanthroline as a ligand. The observed regioselectivity is opposite to that observed from a traditional (nonoxidative) Heck reaction between a vinyl bromide and an alkene. DFT computational studies reveal that steric effects of the 2,9-dimethylphenanthroline ligand promote C-C bond formation at the internal position of the alkene.

SUBMITTER: Zheng C

PROVIDER: S-EPMC3495987 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Catalyst-controlled regioselectivity in the synthesis of branched conjugated dienes via aerobic oxidative Heck reactions.

Zheng Changwu C Wang Dian D Stahl Shannon S SS

Journal of the American Chemical Society 20120928 40

Pd-catalyzed aerobic oxidative coupling of vinylboronic acids and electronically unbiased alkyl olefins provides regioselective access to 1,3-disubstituted conjugated dienes. Catalyst-controlled regioselectivity is achieved by using 2,9-dimethylphenanthroline as a ligand. The observed regioselectivity is opposite to that observed from a traditional (nonoxidative) Heck reaction between a vinyl bromide and an alkene. DFT computational studies reveal that steric effects of the 2,9-dimethylphenanthr ...[more]

PMID: 22998540

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