Dithiols reaction with, phosgene

Thienylthioethanols were obtained in high yields by the reaction of thiophen-2-thiols with ethylene oxide.The reaction of 2,4-dinitro-3-bromothiophen with sodium dimethylthiocarbamate or sodium t-butyl-trithiocarbonate yielded (142). Decomposition of (142b) in glacial acetic acid led to a mixture of (143) and (144) in moderate yield. The reaction of thiophen-3,4-dithiol with phosgene chloride, followed by nitration, gave (145). The reaction of thiophen-2-thiol with p-(methylsulphonyl)bromo-benzene was used for the preparation of 2-thienyl p-(methylsulphonyl)phenyl sulphide. 

Acetylthio-l,2-dithioIylium salts have been described.116 A variety of methods are available for the preparation of 3-halides. The reaction of oxalyl chloride with l,2-dithiol-3-ones gives 3-chloro-l,2-dithiolylium salts (66)116 (Scheme 6). In some cases the reaction can be realized with 1,2-dithiole-3-thiones too. Phosgene can be used instead of oxalyl chloride. Oxalyl bromide gives the corresponding 3-bromo-l,2-dithiolylium salts.117 3-Chloro-l,2-dithiolylium dichlorophosphates have been prepared from 1,2-dithiol-3-ones and phosphorus oxychloride.118 The corresponding... 

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