Hydrolysis of S2F2 A Mechanistic Puzzle

Sulfur forms two stable fluorides— Sp4 and SFg. Of the two, SFg is exceedingly stable, to the point of inertness. By contrast, SF4 is reactive and is used as a fluorinating agent in organic chemistry. In this section, we will focus on a less known sulfur fluoride, S2F2, not because of its inherent importance but because of the complexity of its alkaline hydrolysis, which provides a nice test of our arrow-pushing skills. 

Disulfiir difluoride, S2F2, exists as mixture of two isomers, as shown below. The equi-hbrium is catalyzed by metal fluorides  

Disulfiir difluoride is extremely reactive and is rapidly hydrolyzed by water and alkali  

The reaction is clearly a disproportionation, with part of the sulfur being oxidized to thiosulfate and the rest reduced to elemental sulfur. Beyond this simple observation, however, the mechanism might appear utterly impenetrable. To push arrows, where would one even begin  

An interesting clue is provided by the structural similarity of one of the S2F2 isomers 52O3  

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