Silica-Supported Dichlorophosphate as a Recoverable Cyclodehydrant: Expeditious Synthesis of [1,2,4]Triazolo[3,4-b][1,3,4]thiadiazoles Under Microwave Irradiation

Abstract

An expeditious novel approach to 3,6-disubstituted [1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles using silica-supported dichlorophosphate as a recoverable cyclodehydrant, carboxylic acids and thiocarbohydrazide as starting materials, and microwave irradiation as thermal source was described. The protocol has advantages of concise synthetic step, short time, good yield, easy workup procedure, and no environmental pollution.

Keywords:

• Microwave irradiation
• silica-supported dichlorophosphate
• thiocarbohydrazide
• [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole

ACKNOWLEDGMENTS

The authors thank the National Natural Science Foundation of China (20772096) and Gansu Natural Science Foundation (3ZS061-A25-033) for the financial support of this work.

Notes

^a The yields refer to the isolated product.