N-fluorosulfonimides and their application as fluorinating agents

A process for the electrophilic fluorination of organic compounds which comprises the step of:

• reacting one equivalent of a nucleophilic organic compound with at least one equivalent of a compound of the formula
• R.sub.1 SO.sub.2 --NX--O.sub.2 SR.sub.2
• wherein X represents an isotope or natural isotopic mixture of fluorine, and R.sub.1 and R.sub.2 independently are phenyl or naphthyl, which is unsubstituted or substituted by at least one substituent selected from the group consisting of alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, alkylsulfonyl groups having 1 to 6 carbon atoms, perfluoroalkylsulfonyl groups having 1 to 6 carbon atoms, mono- to per-fluoroalkyl groups having 1 to 6 carbon atoms, cyano, chlorine, and bromine.