Practical Synthesis of NFSI Derivatives through ArSO2NHF without F2

Abstract

Comprehensive SummaryN‐Fluorobenzenesulfonimide (NFSI) is one of the most popular fluorine‐containing reagents for fluorination, imidation, sulfonylation, and oxidation reactions. Consequently, a variety of NFSI derivatives were designed and synthesized to modify the reactivity and/or selectivity of the parent reagent. However, the hazardous F2 was inevitably required for the synthesis of NFSI derivatives. Herein, we disclosed a practical synthesis of various NFSI derivatives without F2 in common organic chemistry laboratories. This synthetic protocol started from NFSI through pyridine‐promoted desulfonylation for formation of N‐fluoroarenesulfonamide (ArSO2NHF) and followed by condensation with arenesulfonyl chlorides. The reduction potentials and fluorinating reactivities of these NFSI derivatives demonstrated that NFSI derivatives bearing the electron‐withdrawing groups on benzene ring had the higher oxidizing and fluorinating abilities than NFSI.