Fluorinating agents silver fluoride

Black silver(II) fluoride, AgF2 (Ag 4- F2), is a strong fluorinating agent. 

The only important compound is the paramagnetic silver(II) fluoride, AgFj, prepared by fluorination of the metal it is used as a convenient fluorinating agent. 

Uses. Silver fluoride has found many laboratory and special industrial appHcations. It is used as a soft (nHld) fluorinating agent for selective fluorination (7—17), as a cathode material in batteries (qv) (18), and as an antimicrobial agent (19). Silver fluoride is commercially available from Advance Research Chemicals, Inc., Aldrich Chemicals, Cerac Corp., Johnson/Matthey, PCR, Atochem, and other sources in the United States. The U.S. price of silver fluoride in 1993 was 1000— 1400/kg and the total U.S. consumption was less than 200 kg/yr. 

Silver difluoride [7783-95-1], AgF2, is a black crystalline powder. It has been classified as a hard fluorinating agent (3) which Hberates iodine from KI solutions and o2one from dilute aqueous acid solutions on heating. It spontaneously oxidizes xenon gas to Xe(II) in anhydrous hydrogen fluoride solutions (20). 

Silver(II) fluoride and potassium tetrafluoroargentate(III) are too powerful as fluorinating agents for tetrahydrofuran and no oxygen-containing products are detected."... 

Silver(I) Fluoride. Silver(I) fluoride, like the mercury fluorides, has been used as a fluorinating agent for many years. It can be used in most of the reactions for which other inorganic fluorides are used. Its use has declined in recent years, primarily because it is deliquescent, light-sensitive, and easily reduced. Only one-half of its fluorine is available for fluorination because it forms the compound AgCl-AgF, which has very little fluorinating power. 

Many metal fluorides beside KF have been tried as nucleophilic fluorinating agents but only a few succeeded in establishing themselves as such. We will briefly survey here fluorides of silver, mercury, cesium and antimony. 

Manganic Fluoride, MnF3, mw 111.94, red, poisonous crysts, sp gr 3 54 mp — decomp on heating sol in acids decomp by w. Can be prepd by dissolving Mn in dil HF contd in a silver basin (Ref 2) and by other methods. Used as a fluorinating agent Refs 1) Gmelin-Kraut, not found 2) Mellor 12(1932), 342 3) CondChemDict (1961),... 

The role of the silver salt is not completely understood. No evidence for a single electron transfer mechanism has been found. Although extremely reactive electrophilic fluorinating agents, such as xenon fluoride triflate (FXeOTf) or trifluoromcthanesulfonyloxy fluoride (TfOF), may be generated from the combination of xenon difluoride and silver(l) triflate, the reaction appears to proceed following initial interaction of the alkcnc with the silver ion. ... 

Silver (II) fluoride, AgF2, made by the action of fluorine on Ag or AgCl, is fairly stable, the equilibrium pressure of fluorine over the solid at 700° being only 80 mm. It is, nevertheless, a useful fluorinating agent. 

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