GREENER SYNTHESIS OF PYRANOPYRAZOLE DERIVATIVES CATALYZED BY CaO NANOPARTICLES

Abstract

We report on the development of a novel green synthetic protocol for the series of pyrano-pyrazole derivatives (5an) in a one-pot multi-component method using CaO nanoparticles as the heterogeneous catalyst. The CaO nanoparticles were synthesized by a greener route using an economic and efficient alternative i.e. papaya leaf extract and exhibited excellent catalytic activity, and this plant-mediated synthesis of CaO nanoparticles is a very promising area of research. CaO nanoparticles can be efficiently used in the synthesis of pyrano-pyrazoles and this catalytic approach can deliver the appropriate products in a rapid reaction time with a high yield (85–91%).The current protocol has various advantages, including a short reaction time, a high percent yield, a clean reaction, a simple separation technique, and a recoverable catalyst that retains its catalytic activity when utilized in subsequent reactions.Characterization of synthesized pyrano-pyrazole derivatives is done by IR, 1H and 13C NMR spectral data as well as HOMO-LUMO calculations.