The reaction of 3-chloropropyl boehmite nanoparticles with caffeine and sulfuric acid afforded BNPs-3-propyl-imidazolopyridinium hydrogen sulfate [BNPs-Caff]HSO4 as a new BNPs-supported ionic liquid (IL) catalyst. [BNPs-Caff]HSO4 proved to be an efficient heterogeneous catalyst for the synthesis of pyrazolopyranopyrimidines via a one-pot four-component reaction of hydrazine hydrate, ethyl acetoacetate, barbituric acid, and an aldehyde. The attractive features […]