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Photo-Initiated Cobalt-Catalyzed Radical Olefin Hydrogenation.

ABSTRACT: Outer-sphere radical hydrogenation of olefins proceeds via stepwise hydrogen atom transfer (HAT) from transition metal hydride species to the substrate. Typical catalysts exhibit M-H bonds that are either too weak to efficiently activate H₂ or too strong to reduce unactivated olefins. This contribution evaluates an alternative approach, that starts from a square-planar cobalt(II) hydride complex. Photoactivation results in Co-H bond homolysis. The three-coordinate cobalt(I) photoproduct binds H₂ to give a dihydrogen complex, which is a strong hydrogen atom donor, enabling the stepwise hydrogenation of both styrenes and unactivated aliphatic olefins with H₂ via HAT.

SUBMITTER: Sang S

PROVIDER: S-EPMC9292329 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Photo-Initiated Cobalt-Catalyzed Radical Olefin Hydrogenation.

Sang Sier S Unruh Tobias T Demeshko Serhiy S Domenianni Luis I LI van Leest Nicolaas P NP Marquetand Philipp P Schneck Felix F Würtele Christian C de Zwart Felix J FJ de Bruin Bas B González Leticia L Vöhringer Peter P Schneider Sven S

Chemistry (Weinheim an der Bergstrasse, Germany) 20210720 68

Outer-sphere radical hydrogenation of olefins proceeds via stepwise hydrogen atom transfer (HAT) from transition metal hydride species to the substrate. Typical catalysts exhibit M-H bonds that are either too weak to efficiently activate H<sub>2</sub> or too strong to reduce unactivated olefins. This contribution evaluates an alternative approach, that starts from a square-planar cobalt(II) hydride complex. Photoactivation results in Co-H bond homolysis. The three-coordinate cobalt(I) photoprodu ...[more]

PMID: 34156122

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