Aza-ring To Build A Complex Synthesis, Structure And Catalytic Properties

The coordination complexes have become increasing significance in the last few years due to the wide variety of potential applications, such as catalysis, magnetism, non-linear optics and so on. However, the research on their catalytic activities is limited. Actually, coordination complexes as catalysts possess lots of potential advantages. The presence of catalytically active transition-metal centers and the porous nature of some coordination complexes may be the basis of shape- and size-selective catalytic applications of such materials. In particular, coordination complexes offer a variety of molecular structures and electronic properties by changing metal ions, ligands, anions, coordination numbers and so on. For example, d orbitals of some transition metals may interact with the organic π electrons to provide a localized electronic system within the complexes. This diversity should give one an opportunity to tune the electronic properties of the molecules, and hence to tune the catalytic activity. In addition, the structures of catalysts should be elucidated in order to fine-tune both catalytic activity and selectivity. The specific structures of self-assembly coordination complexes can be characterized easily by crystallographic analysis, which also gained the priority for practical applications as catalysts.In this paper, we synthesized several coordination complexes and studied their synthesis, structure and evaluation as catalysts. We also obtained a series of coordination polymers according to the articles and examined contrastively their catalysis for a series of oxidation reactions in an aqueous medium with the oxidant aqueous H₂O₂.In the catalytic experiments, we get a series of different conversion and selectivity in the oxidation reaction of phenol in an aqueous medium with the oxidant aqueous H₂O₂. The results show that complex (1) containing Mn(II) presents good catalytic activity in this reaction with a conversion up to 86% and good selectivity of 76% for hydrochinone. While the selectivities for pyrocatechol were better using the complexes containing Fe(II), Cu(II), Co(II) as catalysts, respectively, the maximal conversion of phenol is 68%, 52%, 43% and the selectivity for pyrocatechol is 69%, 59%, 53%, respectively. In addition, the...