Sulfur trioxide reaction with fluorinated compounds

The only methodology pertinent to the formation of 1,2- and 1,3-oxathietanes and their oxidized forms involving S-C and O-C bond formations is that for the preparation of /3-sultones. It is now well established that [7t2s+Jt2s] cycloaddition of sulfur trioxide with an alkene generates /3-sultones in moderate to excellent yields (Equation 1). Indeed, the previous version of this chapter detailed numerous examples of the formation of /3-sultones (especially fluorinated compounds) by the reaction of SO3 with an appropriate alkene at elevated temperatures <1996CHEC-II(1B)1083>. 

Dudley, working with Cady and Eggers, in 1955 obtained fluorine fluorosulfonate by combining sulfur trioxide with fluorine at about 200°, or by the reaction of fluorine with sulfamic acid. The compound is colorless and it has an odor resembling that of oxygen fluoride. It reacts with a solution of sodium hydroxide and with potassium iodide solution according to the equations ... 

The product of Wannagat and Mennicken (314) (see Section III.R.4) contained a small amount of material which was not obtained pure, but had a composition close to S206F2. The properties of this material differed considerably from those of a pure form of S2O6F2, peroxydisulfuryl difluoride, reported in 1957 by Dudley and Cady (77). It is, therefore, not certain that the two substances are the same. The compound is easily produced by the reaction of fluorine with an excess of sulfur trioxide at about 250° or by the reaction of fluorine fluorosulfonate with sulfur trioxide. 

EXPLOSION and FIRE CONCERNS dangerous fire hazard NFPA rating Health 2, Flammability 3, Reactivity 0 explosive reaction with lanthanide perchlorates and nitrogen-fluorine compounds reacts with water, steam, and acids to produce toxic and flammable vapors incompatible with chlorosulfonic acid, nitric acid, sulfur trioxide use foam, carbon dioxide, or dry chemical for firefighting purposes. 

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