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Cobalt bis(acetylacetonate)-tert-butyl hydroperoxide-triethylsilane: a general reagent combination for the Markovnikov-selective hydrofunctionalization of alkenes by hydrogen atom transfer.

ABSTRACT: We show that cobalt bis(acetylacetonate) [Co(acac)₂], tert-butyl hydroperoxide (TBHP), and triethylsilane (Et₃SiH) constitute an inexpensive, general, and practical reagent combination to initiate a broad range of Markovnikov-selective alkene hydrofunctionalization reactions. These transformations are believed to proceed by cobalt-mediated hydrogen atom transfer (HAT) to the alkene substrate, followed by interception of the resulting alkyl radical intermediate with a SOMOphile. In addition, we report the first reductive couplings of unactivated alkenes and aryldiazonium salts by an HAT pathway. The simplicity and generality of the Co(acac)₂-TBHP-Et₃SiH reagent combination suggests it as a useful starting point to develop HAT reactions in complex settings.

SUBMITTER: Ma X

PROVIDER: S-EPMC6122341 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Cobalt bis(acetylacetonate)-tert-butyl hydroperoxide-triethylsilane: a general reagent combination for the Markovnikov-selective hydrofunctionalization of alkenes by hydrogen atom transfer.

Ma Xiaoshen X Herzon Seth B SB

Beilstein journal of organic chemistry 20180828

We show that cobalt bis(acetylacetonate) [Co(acac)2], tert-butyl hydroperoxide (TBHP), and triethylsilane (Et3SiH) constitute an inexpensive, general, and practical reagent combination to initiate a broad range of Markovnikov-selective alkene hydrofunctionalization reactions. These transformations are believed to proceed by cobalt-mediated hydrogen atom transfer (HAT) to the alkene substrate, followed by interception of the resulting alkyl radical intermediate with a ...[more]

PMID: 30202480

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