Synthesis of 2-aryl-5-(benzofuran-2-yl)thiazolo[3,2-b][1,2,4]triazoles using green procedures and their antibacterial activity

3-Aryl-5-(benzofuran-2-yl)acylthio-1,2,4-triazoles 1a-h have been prepared by condensation of 2-(2-bromoacetyl)benzofurans and various 3-aryl-5-mercapto-1,2,4-triazoles under thermal conditions as well as using microwave irradiations and grinding technique. 3-Aryl-5-(benzofuran-2-yl)acylthio-1,2,4-triazoles on cyclisation using polyphosphoric acid under microwave irradiations give 2-aryl-5-(benzofuran-2-yl)-thiazolo[3,2-b][1,2,4]triazoles 2a-h. Preparation of compounds 1a-h using grinding technique and then cyclisation to 2a-h are in accordance to green procedures as these avoid use of hazardous organic solvents during the reaction as well as at its work-up stage. The antibacterial activity of these compounds has been described.