Synthesis,Crystal Structure And Properties Of Pd (Ⅱ) Complex Based On Schiff Bases

Palladium complexes based on Schiff bases have been received increasing recognitiondue to their multiple stuctures and wide variety of potential applications, i.e. bioactivity,catalysis and material. Thus, study on the synthesis of Schiff bases and their metalcomplexes, and their properties and applications has an extremely important significanceon the development of coordination chemistry.In this paper, a series of new Schiff bases and their palladium complexes have beensynthesized and characterized. The Heck reactions of bromobenzene with phenylethylenecatalyzed by complexes1-5have been studied. Moreover, the Schiff bases (L1-L5) andtheir palladium(II) complexes (1-5) have also been screened for their antibacterialactivities against Staphylococcus aureus (S. Aureus) and Rhizopus.1. Five Schiff bases based on benzaldehyde,2,4-dichlorobenzaldehyde and anilinederivatives have been synthesized using solvothermal methods and characterized byelemental analysis, IR spectroscopy, UV-Vis spectroscopy,1HNMR analysis,GC-MS andsingle crystal X-ray diffraction.2. Five palladium(II) complexes (1′,2,3,4,5) based on Schiff bases ligands (L1-L5) andPdCl2have been synthesized using ‘one pot’ solvothermal method. Complex1″wasobtained with the same raw material as1′except that1″was synthesized by solvothermalevaporation method at room temperature. All of six complexes have been characterized byelemental analysis, IR-spectroscopy, thermogravimetric analysis and single-crystal X-raydiffraction.3. Six palladium(II) complexes (1′,1″，2-5) have been shown certain effective in the Heckreaction bromobenzene with acrylic acid, and the results reveal that complex3shown thehighest effect. The optimum conditions of the catalytic reaction of complex3as following:bromobenzene (0.5mmol), phenylethylene (15mmol), complex3(0.5mol%, based onbromobenzene), triethylamine (12mmol), DMF (5mL) and temperature (100°C).4. The Schiff bases (L1-L5) and their palladium(II) complexes (1′,1″，2-5) have been screeced for their antibacterial activities against Staphylococcus aureus (S. Aureus) andRhizopus. The results reveals that the Schiff bases and their palladium(II) complexes showdifferent antibacterial activities and the ligand L3show the highest effect. Compared toSchiff bases, their palladium(II) complexes show better antibacterial activities, which maybe due to the synergistic reaction between Schiff bases and palladium ions.