Masoumeh Balali - Hamedan University of Technology
Razieh Nejat - Chemistry Department, kosar university of bojnord
Majid Rezaeivala - Hamedan University of Technology

A copper complex was immobilized on Schiff base modified magnetic Fe3O4@SiO2 nanoparticles by covalent linkage. The obtainednanoparticles were identified with various characterization methods. The nanocatalyst shows good activity toward Suzuki crosscouplingreaction in environmentally friendly solvent (H2O/DMF) under mild conditions. The catalyst shows not only high catalyticactivity, but also offers many practical advantages such recyclability and air stability. Expectedly, the nanocatalyst can be applied inlarge-scale industrial synthesis.The SEM micrographs of the products Fe3O4 and nanocatalyst are given in Fig. 1(a) and Fig. 1(b) respectively. It was found that thenanoparticles were present as uniform particles with spherical morphology. SEM images reveal that Fe3O4 particles are aggregatedparticles having rough external surfaces (Fig. 1(a)). Silica coating makes the particles exhibit smooth and spongy surfaces (Fig. 1(b))which indicatives the successful coating of silica over the magnetic nanoparticles. However, the nanocatalyst particles still fall in thenano-size range. The reactions were investigated with various aryl halides and arylboronic acids at the determined optimized conditions and the resultsare summarized in Table. The time of reaction for aryl iodide was shorter than aryl bromides and very good to excellent yields wereobtained. It should be noted that the yield of the reaction for aryl iodide and aryl bromides bearing an electron-withdrawing groupwas a little more than electron–releasing group (Table, entries 2-4 and 8-10). We utilized this catalyst in coupling 2-naphthylboronicacid as a larger ring and it was successful (entries 6).

magnetic nanoparticles, cupper complex, Suzuki coupling reaction