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Controllable Isomerization of Alkenes by Dual Visible-Light-Cobalt Catalysis.

ABSTRACT: We report herein that thermodynamic and kinetic isomerization of alkenes can be accomplished by the combination of visible light with Co catalysis. Utilizing Xantphos as the ligand, the most stable isomers are obtained, while isomerizing terminal alkenes over one position can be selectively controlled by using DPEphos as the ligand. The presence of the donor-acceptor dye 4CzIPN accelerates the reaction further. Transformation of exocyclic alkenes into the corresponding endocyclic products could be efficiently realized by using 4CzIPN and Co(acac)₂ in the absence of any additional ligands. Spectroscopic and spectroelectrochemical investigations indicate Co^I being involved in the generation of a Co hydride, which subsequently adds to alkenes initiating the isomerization.

SUBMITTER: Meng QY

PROVIDER: S-EPMC6519376 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Controllable Isomerization of Alkenes by Dual Visible-Light-Cobalt Catalysis.

Meng Qing-Yuan QY Schirmer Tobias E TE Katou Kousuke K König Burkhard B

Angewandte Chemie (International ed. in English) 20190326 17

We report herein that thermodynamic and kinetic isomerization of alkenes can be accomplished by the combination of visible light with Co catalysis. Utilizing Xantphos as the ligand, the most stable isomers are obtained, while isomerizing terminal alkenes over one position can be selectively controlled by using DPEphos as the ligand. The presence of the donor-acceptor dye 4CzIPN accelerates the reaction further. Transformation of exocyclic alkenes into the corresponding endocyclic products could ...[more]

PMID: 30835931

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