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? C-H (hetero)arylation via Cu-catalyzed radical relay.

ABSTRACT: A Cu-catalyzed strategy has been developed that harnesses a radical relay mechanism to intercept a distal C-centered radical for C-C bond formation. This approach enables selective ? C-H (hetero)arylation of sulfonamides via intramolecular hydrogen atom transfer (HAT) by an N-centered radical. The radical relay is both initiated and terminated by a Cu catalyst, which enables incorporation of arenes and heteroarenes by cross-coupling with boronic acids. The broad scope and utility of this catalytic method for ? C-H arylation is shown, along with mechanistic probes for selectivity of the HAT mechanism. A catalytic, asymmetric variant is also presented, as well as a method for accessing 1,1-diaryl-pyrrolidines via iterative ? C-H functionalizations.

SUBMITTER: Zhang Z

PROVIDER: S-EPMC6349054 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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δ C-H (hetero)arylation <i>via</i> Cu-catalyzed radical relay.

Zhang Zuxiao Z Stateman Leah M LM Nagib David A DA

Chemical science 20181109 4

A Cu-catalyzed strategy has been developed that harnesses a radical relay mechanism to intercept a distal C-centered radical for C-C bond formation. This approach enables selective δ C-H (hetero)arylation of sulfonamides <i>via</i> intramolecular hydrogen atom transfer (HAT) by an N-centered radical. The radical relay is both initiated and terminated by a Cu catalyst, which enables incorporation of arenes and heteroarenes by cross-coupling with boronic acids. The broad scope and utility of this ...[more]

PMID: 30774920

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