Phosgene → HCID 21559381, compound

Participants

Reaction Steps

21.7 g (0.1 mol) of 2-(1',1'-difluoro-2',2'-dichloroethyl)-5-amino-1,3,4-thiadiazole were suspended at room temperature in 500 ml of chlorobenzene, and a solution of 30 g of phosgene in 200 ml of chlorobenzene was rapidly added with agitation. With further agitation and feeding-in of gaseous phosgene, the temperature was raised by 15°C per hour until 110°C were attained (a clear solution was obtained from 60°C onward). The solution was then allowed to cool, nitrogen was passed through the solution to remove the residual phosgene, and the solution was concentrated. A brittle mass remained which became pulverulent on trituration with petroleum ether (boiling point 80°-110°C). By suction-filtration and drying, 19 g (73 %) of 2-(1',1'-difluoro-2',2'-dichloro-ethyl)-5-isocyanato-1,3,4-thiadiazole were obtained. Decomposition temperature: 200°C.

Provenance & Evidence