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Isomerization of Olefins Triggered by Rhodium-Catalyzed C-H Bond Activation: Control of Endocyclic ?-Hydrogen Elimination.

ABSTRACT: Five-membered metallacycles are typically reluctant to undergo endocyclic ?-hydrogen elimination. The rhodium-catalyzed isomerization of 4-pentenals into 3-pentenals occurs through this elementary step and cleavage of two C-H bonds, as supported by deuterium-labeling studies. The reaction proceeds without decarbonylation, leads to trans olefins exclusively, and tolerates other olefins normally prone to isomerization. Endocyclic ?-hydrogen elimination can also be controlled in an enantiodivergent reaction on a racemic mixture.

SUBMITTER: Yip SY

PROVIDER: S-EPMC4497606 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Isomerization of Olefins Triggered by Rhodium-Catalyzed C-H Bond Activation: Control of Endocyclic β-Hydrogen Elimination.

Yip Stephanie Y Y SY Aïssa Christophe C

Angewandte Chemie (International ed. in English) 20150423 23

Five-membered metallacycles are typically reluctant to undergo endocyclic β-hydrogen elimination. The rhodium-catalyzed isomerization of 4-pentenals into 3-pentenals occurs through this elementary step and cleavage of two C-H bonds, as supported by deuterium-labeling studies. The reaction proceeds without decarbonylation, leads to trans olefins exclusively, and tolerates other olefins normally prone to isomerization. Endocyclic β-hydrogen elimination can also be controlled in an enantiodivergent ...[more]

PMID: 25907465

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