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? C-H di-halogenation via iterative hydrogen atom transfer.

ABSTRACT: A radical relay strategy for mono- and di-halogenation (iodination, bromination, and chlorination) of sp3 C-H bonds has been developed. This first example of ? C-H di-halogenation is achieved through sequential C-H abstraction by iterative, hydrogen atom transfer (HAT). A double C-H functionalization is enabled by in situ generated imidate radicals, which facilitate selective N? to C? radical translocation and tunable C-X termination. The versatile, geminal di-iodide products are further elaborated to ? ketones and vinyl iodides. Mechanistic experiments explain the unique di-functionalization selectivity of this iterative HAT pathway, wherein the second C-H iodination is twice as fast as the first.

SUBMITTER: Wappes EA

PROVIDER: S-EPMC5958344 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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β C-H di-halogenation via iterative hydrogen atom transfer.

Wappes Ethan A EA Vanitcha Avassaya A Nagib David A DA

Chemical science 20180430 19

A radical relay strategy for mono- and di-halogenation (iodination, bromination, and chlorination) of sp3 C-H bonds has been developed. This first example of β C-H di-halogenation is achieved through sequential C-H abstraction by iterative, hydrogen atom transfer (HAT). A double C-H functionalization is enabled by in situ generated imidate radicals, which facilitate selective N˙ to C˙ radical translocation and tunable C-X termination. The versatile, geminal di-iodide products a ...[more]

PMID: 29896392

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