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Fluorination of 2H-Indazoles Using N-Fluorobenzenesulfonimide

Payel Ghosh and Alakananda Hajra*

*Department of Chemistry, Visva-Bharati (A Central University), Santiniketan 731235, India, Email:

P. Ghosh, A. Hajra, J. Org. Chem., 2021, 86, 10883-10888.

DOI: 10.1021/acs.joc.1c01253

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The use of N-fluorobenzenesulfonimide (NFSI) enables an efficient, simple, and metal-free fluorination of 2H-indazoles in water under ambient air. This transformation provides direct access to fluorinated indazole derivatives with broad functionalities in good yields. The experimental results suggest a radical mechanistic pathway.

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proposed mechanism

Organophotoredox-Catalyzed Direct C-H Amination of 2H-Indazoles with Amines

S. Neogi, A. K. Ghosh, K. Majhi, S. Samanta, G. Kibriya, A. Hajra, Org. Lett., 2020, 22, 5605-5609.

Key Words

2H-Indazoles, NFSI

ID: J42-Y2021