Thiocarbonylimidazolide derivatives

Wharton reaction (1, 439 8, 245). This reaction can also be conducted under free-radical conditions of reduction of thiocarbonylimidazolide derivatives of a,/l-epoxy alcohols with tri-n-butyltin hydride.17 In some cases, inverse addition is necessary to prevent further rearrangement of the allylic alcohol initially formed. Yields are around 50-60%. The modification is not useful in the carbohydrate field, where very complex product mixtures are formed. 

Radical chain chemistry is often employed for the transformation of an alcohol to the corresponding deoxy derivative. The secondary alcohol 1 is first converted into a suitable thiocarbonyl derivative. The first derivatives investigated were thioxobenzoates 2, xan-thates 3, and thiocarbonylimidazolides 4 (Scheme 2). On reduction with tributyltin hydride, these derivatives afforded a good yield of the appropriate deoxy compounds [8-10]. 

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