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Facile Rh(III)-Catalyzed Synthesis of Fluorinated Pyridines.

ABSTRACT: A Rh(III)-catalyzed C-H functionalization approach was developed for the preparation of multisubstituted 3-fluoropyridines from ?-fluoro-?,?-unsaturated oximes and alkynes. Oximes substituted with aryl, heteroaryl, and alkyl ?-substituents were effective coupling partners, as were symmetrical and unsymmetrical alkynes with aryl and alkyl substituents. The first examples of coupling ?,?-unsaturated oximes with terminal alkynes was also demonstrated and proceeded with uniformly high regioselectivity to provide single 3-fluoropyridine regioisomers. Reactions were also conveniently set up in air on the benchtop.

SUBMITTER: Chen S

PROVIDER: S-EPMC4477688 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Facile Rh(III)-Catalyzed Synthesis of Fluorinated Pyridines.

Chen Shuming S Bergman Robert G RG Ellman Jonathan A JA

Organic letters 20150520 11

A Rh(III)-catalyzed C-H functionalization approach was developed for the preparation of multisubstituted 3-fluoropyridines from α-fluoro-α,β-unsaturated oximes and alkynes. Oximes substituted with aryl, heteroaryl, and alkyl β-substituents were effective coupling partners, as were symmetrical and unsymmetrical alkynes with aryl and alkyl substituents. The first examples of coupling α,β-unsaturated oximes with terminal alkynes was also demonstrated and proceeded with uniformly high regioselectivi ...[more]

PMID: 25992591

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