Reactions of 5-substituted 1,3,4-thiadiazole-2-thiones with chloroacetylenephosphonates
摘要:
Reactions of 1-chloroacetylene-2-phosphonates with thiadiazole-2-thiones in anhydrous acetonitrile occur regio- and chemoselectively to form novel fused phosphorus-containing heterocycles, 2-substituted 5-(dialkoxyphosphoryl)thiazolo[2,3-b][1,3,4]thiadiazol-4-ylium chlorides. The formation of these fused cyclic compounds is associated only with the thione form of the starting thiadiazoles. Reactions of the salts of thiadiazole-2-thiols with 1-chloroacetylene-2-phosphonates result in the formation of compounds of linear structure. (C) 2015 Elsevier Ltd. All rights reserved.