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Perfluoroalkylative pyridylation of alkenes via 4-cyanopyridine-boryl radicals.

ABSTRACT: A metal-free and photo-free method for the perfluoroalkylative pyridylation of alkenes has been developed via a combination of computational and experimental studies. Density functional theory calculations and control experiments indicate that the homolysis of R_f-X (X = Br, I) bonds by the 4-cyanopyridine-boryl radicals in situ generated from 4-cyanopyridine and B₂pin₂ is the key step. Sequential addition of R_f radicals to alkenes and the selective cross-coupling of the resulting alkyl radicals and 4-cyanopyridine-boryl radicals gives alkene difunctionalization products with a quaternary carbon center. This method exhibits a broad substrate scope and good functional group compatibility.

SUBMITTER: Cao J

PROVIDER: S-EPMC6419949 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Perfluoroalkylative pyridylation of alkenes via 4-cyanopyridine-boryl radicals.

Cao Jia J Wang Guoqiang G Gao Liuzhou L Chen Hui H Liu Xueting X Cheng Xu X Li Shuhua S

Chemical science 20190116 9

A metal-free and photo-free method for the perfluoroalkylative pyridylation of alkenes has been developed via a combination of computational and experimental studies. Density functional theory calculations and control experiments indicate that the homolysis of Rf-X (X = Br, I) bonds by the 4-cyanopyridine-boryl radicals in situ generated from 4-cyanopyridine and B2pin2 is the key step. Sequential addition of Rf radicals to alkenes and the ...[more]

PMID: 30996995

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