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Hydrogen Atom Transfer-Driven Enantioselective Minisci Reaction of Amides.

ABSTRACT: Minisci-type reactions constitute one of the most powerful methods for building up complexity around basic heteroarenes. The most desirable variants involve formal oxidative coupling of a C-H bond on each partner, leading back to the simplest possible starting materials. We herein disclose a method that enables such a coupling of linear amides and heteroarenes with full control of enantioselectivity at the newly formed stereocenter as well as site selectivity on both the heteroarene and the amide. This is achieved by the use of a chiral phosphoric acid catalyst in conjunction with diacetyl as a combined hydrogen atom transfer reagent and oxidant. Diacetyl is directly photoexcitable, and thus, no extraneous photocatalyst is required: an added feature that contributes to the simplicity and practicality of the protocol.

SUBMITTER: Proctor RSJ

PROVIDER: S-EPMC8033566 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Hydrogen Atom Transfer-Driven Enantioselective Minisci Reaction of Amides.

Proctor Rupert S J RSJ Chuentragool Padon P Colgan Avene C AC Phipps Robert J RJ

Journal of the American Chemical Society 20210329 13

Minisci-type reactions constitute one of the most powerful methods for building up complexity around basic heteroarenes. The most desirable variants involve formal oxidative coupling of a C-H bond on each partner, leading back to the simplest possible starting materials. We herein disclose a method that enables such a coupling of linear amides and heteroarenes with full control of enantioselectivity at the newly formed stereocenter as well as site selectivity on both the heteroarene and the amid ...[more]

PMID: 33780237

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