CuO−La₂O₃ Nanocomposite as a Recyclable and Eco‐Friendly, Heterogeneous Catalyst for the One‐Pot Synthesis of Pyrano [2, 3‐c] Pyrazoles

Abstract

In this work, the unique performance of binary acid‐base CuO/La2O3 nanocomposite as a highly efficient heterogeneous catalyst was successfully examined for the one‐pot multicomponent synthesis of pyrano [2, 3‐c] pyrazole derivatives. The strong interactions between La and Cu had a profound effect on the catalytic activity of nanocatalysts. In addition, high selectivity, easy recovery, reusability, a very reasonable price, simple preparation and eco‐friendliness are other important advantages of this nanocatalyst. The characterized nanocomposite demonstrated excellent structural and morphological properties, leading to high catalytic efficiency. Characterization using Fourier Transform Infrared Spectroscopy (FT‐IR), X‐ray Powder Diffraction (XRD) confirmed crystallographic structure, and Field Emission Scanning Electron Microscopy (FE‐SEM) showed a spherical particle size of approximately 43 nm. Energy‐Dispersive X‐ray (EDX) analysis confirmed the composition of La, O, and Cu elements in the nanocomposite as 86.4 %, 13.5 %, and 0.2 %, respectively. The optimal condition for the synthesis resulted in a 98 % yield of pyrano [2, 3‐c] pyrazole derivatives under reflux with 0.02 g of CuO/La2O3 catalyst in a 10‐minute reaction time.