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Cobalt-catalyzed electrooxidative C-H/N-H [4+2] annulation with ethylene or ethyne.

ABSTRACT: Ethylene and ethyne are among the simplest two-carbon building blocks. However, quite limited methods can be applied to incorporate ethylene or ethyne into fine chemicals. Here we demonstrate a cobalt-catalyzed dehydrogenative C-H/N-H [4+2] annulation of aryl/vinyl amides with ethylene or ethyne by using an electrochemical reaction protocol. Significantly, this work shows an example of electrochemical recycling of cobalt catalyst in oxidative C-H functionalization reactions, avoiding the use of external chemical oxidants and co-oxidants. The electrochemical method provides a reliable and safe way for incorporating gas-phase ethylene or ethyne into fine chemicals. High reaction efficiency and good functional group tolerance are observed under divided electrolytic conditions.

SUBMITTER: Tang S

PROVIDER: S-EPMC5824839 | biostudies-other | 2018 Feb

REPOSITORIES: biostudies-other

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Cobalt-catalyzed electrooxidative C-H/N-H [4+2] annulation with ethylene or ethyne.

Tang Shan S Wang Dan D Liu Yichang Y Zeng Li L Lei Aiwen A

Nature communications 20180223 1

Ethylene and ethyne are among the simplest two-carbon building blocks. However, quite limited methods can be applied to incorporate ethylene or ethyne into fine chemicals. Here we demonstrate a cobalt-catalyzed dehydrogenative C-H/N-H [4+2] annulation of aryl/vinyl amides with ethylene or ethyne by using an electrochemical reaction protocol. Significantly, this work shows an example of electrochemical recycling of cobalt catalyst in oxidative C-H functionalization reactions, avoiding the use of ...[more]

PMID: 29476057

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