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Site-Selective Pd-Catalyzed C(sp³ )-H Arylation of Heteroaromatic Ketones.

ABSTRACT: A ligand-controlled site-selective C(sp³ )-H arylation of heteroaromatic ketones has been developed using Pd catalysis. The reaction occurred selectively at the α- or β-position of the ketone side-chain. The switch from α- to β-arylation was realized by addition of a pyridone ligand. The α-arylation process showed broad scope and high site- and chemoselectivity, whereas the β-arylation was more limited. Mechanistic investigations suggested that α-arylation occurs through C-H activation/oxidative addition/reductive elimination whereas β-arylation involves desaturation and aryl insertion.

SUBMITTER: Kudashev A

PROVIDER: S-EPMC9299137 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Site-Selective Pd-Catalyzed C(sp3 )-H Arylation of Heteroaromatic Ketones.

Kudashev Anton A Baudoin Olivier O

Chemistry (Weinheim an der Bergstrasse, Germany) 20211111 70

A ligand-controlled site-selective C(sp3 )-H arylation of heteroaromatic ketones has been developed using Pd catalysis. The reaction occurred selectively at the α- or β-position of the ketone side-chain. The switch from α- to β-arylation was realized by addition of a pyridone ligand. The α-arylation process showed broad scope and high site- and chemoselectivity, whereas the β-arylation was more limited. Mechanistic investigations suggested that α-arylation occurs through C-H activatio ...[more]

PMID: 34761844

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