N-Fluorobenzenesulfonimide [NFSI] is a stable crystalline solid that easy to handle, non-hygroscopic, soluble in most common ethereal and chlorinated solvents, and commercially available. It is a neutral N–F-containing electrophilic fluorinating agent that permits the incorporation of fluorine into neutral and carbanionic nucleophiles ranging from very reactive organometallic species to slightly activated aromatic compounds.1 N-Fluorobenzenesulfonimide can be employed in the preparation of aryl (difluoromethylenephosphonates),2 20-deoxy-20-fluorocamptothecin,3 N-fluoro sulfonamides, 4 2-amino-5-fluorothiazole hydrochloride5 and benzylic a,a-difluoronitriles, -tetrazoles, and -sulfonates.6 When NFSI was associated with chiral palladium complexes an efficient method to catalytic enantioselective fluorination of b-keto esters,7 and a-cyano acetates8 was presented.
