A NEW EFFICIENT ROUTE TO IMIDAZO4,5-CPYRAZOL-5-ONES

摘要

The synthesis of imidazo4,5-cpyrazol-5-ones (6) is reported. 5-Amino-4-ethoxycarbonylaminopyrazoles 3a-g when heated at 200 degrees for 2 hours afford 6a-g. In a similar manner imidazo4,5-cpyrazol-5-one (6a) is readily obtained from 4-amino-5-ethoxycarbonylaminopyrazole (5a). References: 20