NiO nanoparticles: A highly efficient catalyst for the one-pot three-component synthesis of pyrano [2, 3-d] pyrimidine derivatives in green media.

: NiO nanoparticles are utilized to effectively strengthen annulated pyrano [2, 3- d] pyrimidine synthesis through primary Knoevenagel, following Micheal and ultimate heterocyclization reactions of aldehyde, malononitrile, and barbituric acid. The characteristics of NiO nanoparticles are identified using advanced techniques, such as IR, UV, EDX, XRD, SEM, and TEM. The nano-NiO particles are mostly below < 100 nm in size with uniform spherical shapes. The adopted approach is advantages thanks to its simple processing, relatively short reaction time, often good to high average yields, convenient workability, and environmental friendliness.