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Reaction Pathways and Redox States in ?-Selective Cobalt-Catalyzed Hydroborations of Alkynes.

ABSTRACT: Cobalt(II) alkyl complexes supported by a monoanionic NNN pincer ligand are pre-catalysts for the regioselective hydroboration of terminal alkynes, yielding the Markovnikov products with ?:?-(E) ratios of up to 97:3. A cobalt(II) hydride and a cobalt(II) vinyl complex appear to determine the main reaction pathway. In a background reaction the highly reactive hydrido species specifically converts to a coordinatively unsaturated cobalt(I) complex which was found to re-enter the main catalytic cycle.

SUBMITTER: Blasius CK

PROVIDER: S-EPMC7756293 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Reaction Pathways and Redox States in α-Selective Cobalt-Catalyzed Hydroborations of Alkynes.

Blasius Clemens K CK Vasilenko Vladislav V Matveeva Regina R Wadepohl Hubert H Gade Lutz H LH

Angewandte Chemie (International ed. in English) 20201015 51

Cobalt(II) alkyl complexes supported by a monoanionic NNN pincer ligand are pre-catalysts for the regioselective hydroboration of terminal alkynes, yielding the Markovnikov products with α:β-(E) ratios of up to 97:3. A cobalt(II) hydride and a cobalt(II) vinyl complex appear to determine the main reaction pathway. In a background reaction the highly reactive hydrido species specifically converts to a coordinatively unsaturated cobalt(I) complex which was found to re-enter the main catalytic cycl ...[more]

PMID: 32889757

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