Thiocarbamic esters thiourethanes

A variety of methods is available for preparation of O-esters of thiocarbamic acid  

Reaction (1) is advantageous only when R = alkyl,781 (2) gives good yields with alcohols but not with phenols,782-785 results with (3) are good only for disubstituted carbamoyl chlorides,786 and (4) is by far the most generally applicable.783 787 788 

0-Aryl TV-substituted thiocarbamates 787 An 0-aryl chlorothioformate (1 mole) is dropped slowly into a solution of an amine (2 moles) in acetone or ethanol at 20-30°, with stirring. After a further hour s stirring, the mixture is poured into water, and the precipitated ester is collected, dried, and recrystallized from ethanol. 

5-esters of thiocarbamic acid can be obtained by modification of the methods indicated above, namely, from carbamoyl chlorides and thiolates789 from 5-esters of chlorothioformic acid and amines,790 or by addition of water to thiocyanic esters.791 

Dithiocarbamic esters can generally be obtained easily by alkylation or arylation of the corresponding dithiocarbamic salts 792-798 other methods are addition of thiols to isothiocyanic esters,792 treatment of chlorodithio-formic esters with amines,792 and reaction of thiocarbamoyl chlorides with thiolates.786 

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Hydroxythiazoles give 2-chIorothiazole derivatives almost quantitatively upon treatment with phosphorus oxychloride (221, 229, 428). This constitutes a convenient synthesis method for these compounds when the conversion of 2-aminothiazoles to 2-chlorothiazole derivatives fails. Esters of thiocarbamic acid or thiourethanes also react with a-halocarbonyl compounds to give the corresponding 2-alkoxythiazoles (50, 68, 209, 272). 

Thiourethans (s. a. Dithio-urethans, Thiocarbamic acid esters)... 

S-Et ester [637-98-9]. S-Ethyl carbamothioate, 9CI. S-Ethyl thiocarbamate, SCI. S-Ethyl aminothioformate. Thiourethane... 

O-Et ester [625-57-0]. O-Ethyl carbamothioate, 9CI. O-Ethyl thiocarbamate, SCI. O-Ethyl aminothioformate. Xanthogenamide. Thiourethane C3H7NOS M 105.160... 

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