Thiocarbonic diesters

Thiocarbonic diesters are prepared by treating 2 moles of an alcohol or thiolate with one mole of phosgene or thiophosgene or by treating an alkoxide or thiolate with a chlorothioformic ester in 1 1 molar ratio, according to the following reactions where M = metal  

0-Diaryl thiocarbonates 756,759 A monohydric phenol (2 moles) is dissolved in a small excess of 10% sodium hydroxide solution, diluted with the four- to five-fold amount of water, and treated gradually, with vigorous shaking, with thiophosgene (1 mole). If the mixture becomes too warm it must be cooled. The aryl ester produced separates as a white precipitate and is washed free from alkali by water and recrystallized, generally from ethanol. 

Diphenyl thiocarbonate obtained in this way in almost quantitative yield has m.p. 106°. 

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The reaction of alkyl isothiocyanates, RNCS, with diphenylphosphinic hydrazide (338) in benzene has been reported.308 The bis(diethylamino)[(methylthio)thiocarbon-yl]carbenium salts (339 X = I or BF4) display ambident reactivity and can react either at carbenium carbon (hard nucleophiles) or at the thiocarbonyl sulfur atom (soft nucleophiles).309 Electrochemically generated superoxide reacts with dithioic S,S -diesters (dicarbothiolates) (340 Ar = C5H3N or C6H4) to give the monocarboxylate anions in 100% yield before giving the dicarboxylate anions.310... 

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