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Ring-size-selective construction of fluorine-containing carbocycles via intramolecular iodoarylation of 1,1-difluoro-1-alkenes.

ABSTRACT: 1,1-Difluoro-1-alkenes bearing a biaryl-2-yl group effectively underwent site-selective intramolecular iodoarylation by the appropriate cationic iodine species. Iodoarylation of 2-(2-aryl-3,3-difluoroallyl)biaryls proceeded via regioselective carbon-carbon bond formation at the carbon atoms in ?-position to the fluorine substituents, thereby constructing dibenzo-fused six-membered carbocycles bearing a difluoroiodomethyl group. In contrast, 2-(3,3-difluoroallyl)biaryls underwent a similar cyclization at the ?-carbon atoms to afford ring-difluorinated seven-membered carbocycles.

SUBMITTER: Fujita T

PROVIDER: S-EPMC5753149 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Ring-size-selective construction of fluorine-containing carbocycles via intramolecular iodoarylation of 1,1-difluoro-1-alkenes.

Fujita Takeshi T Kinoshita Ryo R Takanohashi Tsuyoshi T Suzuki Naoto N Ichikawa Junji J

Beilstein journal of organic chemistry 20171214

1,1-Difluoro-1-alkenes bearing a biaryl-2-yl group effectively underwent site-selective intramolecular iodoarylation by the appropriate cationic iodine species. Iodoarylation of 2-(2-aryl-3,3-difluoroallyl)biaryls proceeded via regioselective carbon-carbon bond formation at the carbon atoms in β-position to the fluorine substituents, thereby constructing dibenzo-fused six-membered carbocycles bearing a difluoroiodomethyl group. In contrast, 2-(3,3-difluoroallyl)biaryls underwent a similar cycliz ...[more]

PMID: 29564005

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