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Development of an Imine Chaperone for Selective C-H Functionalization of Alcohols via Radical Relay.

ABSTRACT: The design of a radical relay chaperone to promote selective C-H functionalizations is described. A saccharin-based imine was found to be uniquely suited to effect C-H amination of alcohols via an in situ generated hemiaminal. This radical chaperone facilitates the mild generation of an N-centered radical while also directing its regioselective H atom transfer (HAT) to the ? carbon of an alcohol. Upon ? C-H halogenation, aminocyclization, and reductive cleavage, an NH2 is formally added vicinal to an alcohol. The development, synthetic utility, and chemo-, regio-, and stereoselectivity of this imine chaperone-mediated C-H amination is presented herein.

SUBMITTER: Nakafuku KM

PROVIDER: S-EPMC6948922 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Development of an Imine Chaperone for Selective C-H Functionalization of Alcohols via Radical Relay.

Nakafuku Kohki M KM Twumasi Raymond K RK Vanitcha Avassaya A Wappes Ethan A EA Namitharan Kayambu K Bekkaye Mathieu M Nagib David A DA

The Journal of organic chemistry 20190912 20

The design of a radical relay chaperone to promote selective C-H functionalizations is described. A saccharin-based imine was found to be uniquely suited to effect C-H amination of alcohols via an <i>in situ</i> generated hemiaminal. This radical chaperone facilitates the mild generation of an N-centered radical while also directing its regioselective H atom transfer (HAT) to the β carbon of an alcohol. Upon β C-H halogenation, aminocyclization, and reductive cleavage, an NH<sub>2</sub> is forma ...[more]

PMID: 31513401

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