N-Fluorobenzenesulfonimide NEW

Description:

NFSI is a new, stable and mild fluorination reagent, which can introduce fluorine atoms into the carbonyl o-site of organic molecules, and can monofluorinate electron-rich aromatic compounds, enolsilthers, enollithium salts, etc. Current research focuses on the formation of five-membered ring Nazarov cyclization catalyzed by iron or cobalt, asymmetric catalysis of enantioselective α-fluorination.

Preparation:

There are two main methods for the production of N-fluorodiphenylsulfonamide. The first method is Differding. The specific preparation process is as follows: Dibenzenesulfonimide was dissolved in acetonitrile, sodium fluoride was added, the mixture was cooled to -35℃, and the fluorine nitrogen mixture with a volume ratio of 1:10 was breathed into the mixture for 2 hours, then the nitrogen gas was purred for 2 hours, and white crystals were obtained through filtration, evaporation and recrystallization. The yield was 74%. The other is Wanger method, the specific preparation process is: diphenyl sulfonimide sodium salt dissolved in water/acetonitrile or pure water, cooled into the V(F2):V(N2) = 1:10 fluorine nitrogen mixture, after the reaction is over with nitrogen purgatory reactor, filtered, washed, dried to obtain N-fluorinated diphenyl sulfonamide products, the yield of up to 94%.

Uses:

N-fluorobenzylsulfonamide can be used for palladium-catalyzed enantioselective fluorination of tert-butoxycarbonyl lactones and lactam compounds. It can also be used for electrophilic difluorination of dihalopyridine compounds under the action of butyl lithium, and for direct conversion of alcohols under the action of triphenylphosphine to diphenyl sulfonimide compounds. Stable and easy to handle crystalline material, easy to convert F+ into enolates and negative carbon ions.