First synthesis of bis[1,2,3]triazolo[1,5-b;5 ',1 '-f][1,3,6]thiadiazepinederivatives by [2+1] condensation of 1,2,3-thiadiazoles with vicinal diamines

Novel bistriazolo[1,3,6]thiadiazepine derivatives have been prepared by the base-catalyzed condensation of aromatic and aliphatic 1,2-diamines with 5- chloro-1,2,3-thiadiazoles, via a multistep process which is thought to invo lve two Dimroth rearrangements and subsequent loss of hydrogen sulfide by i ntramolecular nucleophilic substitution.