Ethylene sulphite, hydrolysis

The kinetics of hydrolysis in alkaline solution show that no appreciable reversible ring opening occurs. However, when a solvent containing 0-94 atom % excess O18 was used, it was found that the recovered ethylene sulphite contained 0-016 atom % excess O18. Bunton et al. interpreted this result as indicating no significant exchange but Davis (1962) considers that these same results prove the formation of a tetracovalent intermediate. Further work is needed to settle this point. 

Another method for the hydroxylation of the ethylenic linkage consists in treatment of the alkmie with osmium tetroxide in an inert solvent (ether or dioxan) at room temperature for several days an osmic ester is formed which either precipitates from the reaction mixture or may be isolated by evaporation of the solvent. Hydrolysis of the osmic ester in a reducing medium (in the presence of alkaline formaldehyde or of aqueous-alcoholic sodium sulphite) gives the 1 2-glycol and osmium. The glycol has the cis structure it is probably derlv from the cyclic osmic ester ... 

No exchange was found in the acid- or base-catalysed hydrolysis of ethylene (44) and trimethylene sulphite (45) (Bunton et al., 1958a). The result in acid solution indicates that no tetracovalent intermediate is formed and also that reversible ring opening does not occur. 

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