A Novel Magnetic Immobilized Para-Aminobenzoic Acid-Cu(II) Complex: A Green, Efficient and Reusable Catalyst for Aldol Condensation Reactions in Green Media

In this the study a novel, efficient and recoverable heterogeneous nanocatalyst with regards to green chemistry purpose was approached. The structure of the newly synthesized heterogeneous magnetic nanocatalyst with enhanced and improved catalytic efficiency were determined by various instrumental techniques, including SEM, VSM, TGA, XRD, UV–VIS FT-IR and EDXA. The results, showed that the synthesized nanoparticles are superparamagnetic with a size range of 10–20 nm. Then the catalytic activity and efficient performance of Fe 3 O 4 @PABA-Cu(II) MNPs were analyzed toward the synthesis of novel 5-arylidenthiazolidine-2,4-diones and 5-arylidene-2-imidazolidine-2,4-dione derivatives via aldol condensation reactions between a variety of (hetero) aromatic aldehydes and hydantoin or thiazolidine-2,4-dione multifunctional privileged scaffolds under reflux condensations in ethanol as a benign solvent. Nontoxic nature and environment-friendly properties of the catalyst, simple workup, short time of reaction, easy separation of the catalyst from products, efficiency, and excellent yields are beneficial aspects of this method. Graphic Abstract It is the first report of aldol synthesis of new 5-arylidenthiazolidine-2,4-dione, and 5-arylidene-imidazolidine-2,4-dione derivatives using a reusable copper-PABA complex supported on Fe 3 O 4 MNPs (Fe 3 O 4 @PABA-Cu(II)) catalyst in Green media.