Silica sulfuric acid catalyzed an efficient and green protocol for the synthesis of 2-amino-5-aryl-1, 3, 4-thiadiazole

Abstract

This study has been undertaken to investigate an efficient and green protocol for the cyclocondensation of substituted aromatic carboxylic acids 1a-i and thiosemicarbazide 2 under solvent-free conditions using silica sulfuric acid (SSA) as a catalyst. Mild reaction conditions with high yield, fast rate of reaction, avoidance of toxic acids, Reusability of catalysts are significant advantages which make this method safe, convenient, economical and environmentally friendly for synthesis of 2-amino-5-aryl-1, 3, 4-thiadiazole 3a-i. The structures of the compounds have been confirmed by 1H-NMR, 13C-NMR & FT-IR spectroscopic techniques.