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Cobalt-catalyzed radical-mediated carbon-carbon scission via a radical-type migratory insertion.

ABSTRACT: Migratory insertions of alkenes into metal-carbon (M-C) bonds are elementary steps in diverse catalytic processes. In the present work, a radical-type migratory insertion that involves concerted but asynchronous M-C homolysis and radical attack was revealed by computations. Inspired by the radical nature of the proposed migratory insertion, a distinct cobalt-catalyzed radical-mediated carbon-carbon (C-C) cleavage mechanism was proposed for alkylidenecyclopropanes (ACPs). This unique C-C activation is key to rationalizing the experimentally observed selectivity for the coupling between benzamides and ACPs. Furthermore, the C(sp²)-H activation in the coupling reaction occurs via the proton-coupled electron transfer (PCET) mechanism rather than the originally proposed concerted metalation-deprotonation (CMD) pathway. The ring opening strategy may stimulate further development and discovery of novel radical transformations.

SUBMITTER: Liu JB

PROVIDER: S-EPMC10033940 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Cobalt-catalyzed radical-mediated carbon-carbon scission <i>via</i> a radical-type migratory insertion.

Liu Jian-Biao JB Liu Xiao-Jun XJ Oliveira João C A JCA Chen De-Zhan DZ Ackermann Lutz L

Chemical science 20230228 12

Migratory insertions of alkenes into metal-carbon (M-C) bonds are elementary steps in diverse catalytic processes. In the present work, a radical-type migratory insertion that involves concerted but asynchronous M-C homolysis and radical attack was revealed by computations. Inspired by the radical nature of the proposed migratory insertion, a distinct cobalt-catalyzed radical-mediated carbon-carbon (C-C) cleavage mechanism was proposed for alkylidenecyclopropanes (ACPs). This unique C-C activati ...[more]

PMID: 36970104

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