A novel protocol for selective synthesis of monoclinic zirconia nanoparticles as a heterogeneous catalyst for condensation of 1,2-diamines with 1,2-dicarbonyl compounds

ZrO2 nanocatalyst has been obtained successfully using novel and safe agents through a simple and safe sol–gel method (polymerizing–complexing) and characterized by XRD, FT-IR, Raman spectroscopies and transmission electron microscopy (TEM). Raman spectroscopies and XRD results indicated only formation of monoclinic zirconia. TEM images revealed spherical nanoparticles with 20–40 nm diameter range. The spectral and analysis data confirmed the effectiveness of the method for preparation of monoclinic zirconia by preventing grain growth or agglomeration of particles. The nanostructured ZrO2 exhibited high efficiency in catalyzing condensation of various 1,2-diamine and 1,2-dicarbonyl compounds for the synthesis of heterocyclic compounds. The recovery of the title heterogeneous nanocatalyst was easy and efficient and its catalytic activity was strikingly different from the bulk one.