Microwave Assisted Synthesis of Some 4-Amino-5-substituted Aryl-3-mercapto-(4H)-1,2,4-triazoles

Abstract

The conventional and microwave synthesis of twenty eight 4-amino-5-substituted aryl-3-mercapto-(4H)-1,2,4-triazoles (V) were studied and compared. Methyl esters of the substituted benzoic acids (II) were made to its respective hydrazides (III) by treating with hydrazine hydrate. These hydrazides were then treated with alcoholic potassium hydroxide and carbon disulphide to obtain the respective aryl dithiocarbazinic acid salts (IV). These salt were cyclized under conventional and microwave condition separately to the corresponding 4-amino- 5-aryl-3-mercapto-(4H)-1,2,4-triazole. The structures of final compounds (V) were confirmed by elemental analysis, IR and ¹H NMR.