Redox properties of electrophilic fluorination reagents of the N-F class

140

All Electrophilic

fluorinating

agents of the N-F

class

R. E. Banks Department

of Chemistry,

UMIST, Manchester

M60 IQD (UK)

Recent progress in the development of site-specific electrophilic fluorinating agents of the N-F class will be reviewed. Emphasis will be placed on (1 -ah@-4-fluoro- 1,4-diazoniabicyclocompounds of the SELECTFLUORm (2.2.2loctane salts) (1) and 4,4’-bipyridinium (2) classes (R=alkyl, haloalkyl; X = BFI - , CFBSOB-).

F

w-1,

Cl1

CZ)

AI.2 Redox properties the N-F class Guido P. Pez, Andrew Corporate Research

of electrophilic

fluorination

reagents of

G. Gilicinski, Robert G. Syvret and G. Sankar Lal

Group, Air Products and Chemicals,

Inc., Allentown,

PA 18195

(USA)

Electrophilic fluorination reagents, especially compounds of the type R,N+-F A- and R3N-F are increasingly employed for the synthesis of biologically active molecules. The reagents’ inherent oxidizing properties have been quantified by electrochemical measurements. A correlation was found between their one-electron reduction and their chemical reactivity in synthetic fluorination reactions, thus permitting a ranking of the relative fluorinating power of the compounds. Various synthetic applications which exploit the redox properties of the reagents will be discussed.