Efficient Ag/La-ZnO core-shell catalyst for green synthesis of 4-pyrano[2,3-] pyrazoles.

The advancement of green and efficient synthetic strategies is essential for the pursuit of environmentally sustainable organic transformations. Pyrazole derivatives, recognized for their broad pharmacological and synthetic utility, are key structural motifs in various bioactive molecules. This study reports a one-pot, four-component (aryl aldehyde, malononitrile, ethyl acetoacetate, and hydrazine hydrate) synthesis of pyrazole derivatives catalyzed by lanthanum-doped and silver-coated ZnO (Ag/La-ZnO) core-shell nanoparticles under solvent-free grinding conditions at ambient room temperature.