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Controlled chemoselective defluorination and non-defluorination for [5 + 1] aromatic annulation via Meisenheimer-type nitrogen anion and radical intermediates.

ABSTRACT: Reported is a unique chemoselectivity approach to base-promoted defluorinative and Cu(i)-catalyzed aerobic oxidative non-defluorinative [5 + 1] condensation aromatizations of simple unsaturated ketones with ammonium salts via Meisenheimer-type nitrogen anion and radical intermediates. The CuBr/O2 catalysis provides a straightforward approach to diverse 3-fluoropyridines in high yields. The synthetic utility of the strategy is highlighted by the concise synthesis of several F-modified bioactive compounds.

SUBMITTER: Qian J

PROVIDER: S-EPMC6853080 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Controlled chemoselective defluorination and non-defluorination for [5 + 1] aromatic annulation via Meisenheimer-type nitrogen anion and radical intermediates.

Qian Jinlong J Zhang Jinlong J Yang Huameng H Kang Lei L Jiang Gaoxi G

Chemical science 20190807 38

Reported is a unique chemoselectivity approach to base-promoted defluorinative and Cu(i)-catalyzed aerobic oxidative non-defluorinative [5 + 1] condensation aromatizations of simple unsaturated ketones with ammonium salts via Meisenheimer-type nitrogen anion and radical intermediates. The CuBr/O2 catalysis provides a straightforward approach to diverse 3-fluoropyridines in high yields. The synthetic utility of the strategy is highlighted by the concise synthesis of several F-mo ...[more]

PMID: 31803454

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