1-Chlorothioformimidinium chlorides

Chlorothioformimidinium chlorides general procedure) C ). To the solution of 1 mole of the N,N-disubstituted dithiocarbamate in 400-700 ml of toluene at 20-30°C approximately 1.5-2.0 moles of phosgene is added. After standing for several hours at room temperature, dry diethyl ether is added and the obtained 1-chlorothioformimidinium chlorides are collected by filtration. The obtained yields range from 72-100%. 

The hydrolysis of 1-chlorothioformimidinium chlorides with excess sodium carbonate affords N,N-disubstituted thiocarbamic acid S-esters XXVIII ( ). 

In the reaction of 1-chlorothioformimidinium chlorides with phenols a mixture of thiocarbamic O-esters XXXIV and alkyl halides is obtained (" I. 

The reaction of 1-chlorothioformimidinium chlorides with primary amines or sulfonamides in the presence of a base affords the isothiourea derivatives XXXIX ( ). 

The reaction of acid hydrazides XLV with 1-chlorothioformimidinium chlorides occurs at room temperature with formation of the initial polar reaction products XLVI, which readily cyclize to form 1,3,4-oxadiazoles XLVII ( ). 

The choice of the basicity of the solvent used in this reaction (pyridine, N-methylpyrrolidone) determines its course. While in pyridine the amino-1,3,4-oxadiazoles are formed, 2-mercapto derivatives are obtained in N-methylpyrrolidone. Similarly, amidoximes XLVIII, on reaction with 1-chlorothioformimidinium chlorides, yield either 2-amino-1,2,4-oxadiazoles XLIX or the 2-mercapto derivatives L C ). 

The reaction of 1-chlorothioformimidinium chlorides with nucleophilic carbon atoms results in the formation of a carbon-carbon bond. For example, reaction of 1-chlorothioformimidinium chlorides with malonitrile yields the ketene S,N-acetals LIV C "). 

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