The surface ofFe3O4 magnetic nanoparticles (MNPs) was modified by L-cysteine through condensation of COOH groups of L-cysteine and OH groups on the surface of Fe3O4. The –SH group of preparedFe3O4@Cys MNPs oxidized to –SO3H group and Fe3O4@Cys–SO3H as an environmentally friendly magnetic nanoparticle was prepared. The MNPs were characterized by FT-IR, XRD, SEM and TEM studies. Then, the catalytic activity of the MNPs was evaluated as an effective and reusable catalyst for one-pot synthesis of 2H‐indazolo [1,2‐b] phthalazine‐triones derivatives. The results show that the catalytic activity of Fe3O4@Cys–SO3H was comparable to that of other reported heterogeneous and homogeneous catalysts. تفاصيل المقالة

Densely functionalized 3,4-dihydropyridones were synthesized by a four-component reaction of Meldrumʼs acid, ethyl acetoacetate, ammonium acetate, and proper aromatic aldehydes in the presence of novel organic-inorganic cobalt incorporated magnetic nanocatalyst (γ-Fe2O3@HAp/Co(II)) using ethanol as a green solvent at reflux condition. This new synthetic method provided the target compounds in a high yield (70-95%) and lower reaction time (20-75 min). The protocol benefits from the high purity of the products, environmentally friendly, milder reaction conditions, recyclability of the catalyst, and facile workup procedure. The structure of the synthesized novel nanocatalyst was confirmed by FT-IR, XRD, FSEM, TEM, EDS, and TGA analyses. The catalyst was used in eight cycles without any notable variation in catalytic activities. تفاصيل المقالة