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Ring-opening fluorination of bicyclic azaarenes.

ABSTRACT: We have discovered a ring-opening fluorination of bicyclic azaarenes. Upon treatment of bicyclic azaarenes such as pyrazolo[1,5-a]pyridines with electrophilic fluorinating agents, fluorination of the aromatic ring is followed by a ring-opening reaction. Although this overall transformation can be classified as an electrophilic fluorination of an aromatic ring, it is a novel type of fluorination that results in construction of tertiary carbon-fluorine bonds. The present protocol can be applied to a range of bicyclic azaarenes, tolerating azines and a variety of functional groups. Additionally, mechanistic studies and enantioselective fluorination have been examined.

SUBMITTER: Komatsuda M

PROVIDER: S-EPMC8768879 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Ring-opening fluorination of bicyclic azaarenes.

Komatsuda Masaaki M Suto Ayane A Kondo Hiroki H Takada Hiroyuki H Kato Kenta K Saito Bunnai B Yamaguchi Junichiro J

Chemical science 20211221 3

We have discovered a ring-opening fluorination of bicyclic azaarenes. Upon treatment of bicyclic azaarenes such as pyrazolo[1,5-<i>a</i>]pyridines with electrophilic fluorinating agents, fluorination of the aromatic ring is followed by a ring-opening reaction. Although this overall transformation can be classified as an electrophilic fluorination of an aromatic ring, it is a novel type of fluorination that results in construction of tertiary carbon-fluorine bonds. The present protocol can be app ...[more]

PMID: 35173930

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