One-pot synthesis of novel pyrazolo[4,3-e][1,2,4]triazolo[1,5-c] pyrimidines under microwave irradiation in a green solvent

A one-pot microwave-assisted method for the synthesis of pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimi-dines from 5-aminopyrazolyl-4-carbonitriles, orthoesters, and hydrazides was developed. The method utilizes anisole as a geen media for the reaction and tolerates variations in the structure of each substrate, thus allowing the preparation of diverse pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidines. The catalyst-free one-pot protocol, short reaction time, and convenient work-up are additional beneficial features of this method.& COPY; 2023 Elsevier Ltd. All rights reserved.

Automated summary

A microwave-assisted method was developed for the synthesis of pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidines from 5-aminopyrazolyl-4-carbonitriles, orthoesters, and hydrazides in one pot. The method uses anisole as a green media and allows for diverse pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine preparation with variations in the structure of each substrate. The catalyst-free one-pot protocol, short reaction time, and convenient work-up are additional advantageous features of this method.