H₁₄[NaP₅W₃₀O₁₁₀] as a Heterogeneous Recyclable Catalyst for the Synthesis of 6,8-Dimethyl-3-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiazepine Derivatives

Abstract

6,8-Dimethyl-3-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiazepine derivatives were synthesized by cyclodehydration of 3-aryl-4-amino-5-mercapto-1,2,4-triazole with 2,4-pentanedione in the presence of a catalytic amount of Preyssler catalyst under very mild conditions.

Keywords:

• 3-Aryl-4-amino-5-mercapto-1,2,4-triazole
• heteropolyacids
• 2,4-pentanedione
• Preyssler catalyst

ACKNOWLEDGMENT

The authors are thankful to Alzahra Research Council for the partial financial support.

Notes

Notes. Method A: refluxed at 90 °C for 1.5 h in solvent-free conditions in the presence of Preyssler catalyst. Method B: refluxed in acetic acid for 4 h.