Boehmite nanoparticle supported –SO3H as recyclable heterogeneous Catalyst for the efficient one‐pot synthesis of Pyrazolo [1,2-a][1,2,4]triazole-1,3-diones

One-Pot multi-component reactions have proven to be more advantageous over conventional linear-type synthesis [1] since the multi-step reactions are usually subjected to compel isolation procedures and produce significant amounts of waste materials. In addition,multi-component processes provide rapid and efficient approach to organic transformations including diverse synthesis of polyfunctionalizedheterocycles. A wide range of naturally occurring compounds belongs to nitrogen-containing heterocyclic compounds. Many of these heterocycles are of significant biological and synthetic importance, which act as pharmaceuticals, agrochemicals, and polyfunctionalized fragments [2,3]. Among these heterocyclic compounds, 1,2,4 triazolidine-3,5-dione containing heterocycles, so-called urazoles, have received considerable interest in synthetic and industrial chemistry [4]. A facile and efficient One-Pot three component synthesis of pyrzolo [1,2-a][1,2,4] triazolo-1,3-diones via condensation reaction between aldehyde, 4- phenylurazole and malonitrile or ethylcyanoacetate in ethanol catalyzed byboehmite supported –SO3H was developed. This method gave good to excellent yields, has short reaction time, operational simplicity and a recyclable catalyst.