Synthesis, Crystal Structures And Self-assembly Of Transition Metal Complexes With Schiff Bases

In recent years, Schiff base complexes have play an important role in the development of coordination chemistry related to catalysis reaction, medicine, analytical chemistry and many other fields. Schiff base complexes have attracted much attention due to their versatile properties. Studying the Schiff base complexes, we should not only consider the functional starting materials, their formation mechanisms, and spectra character, but should also consider their properties. Studying the synthesis, structures and interactions between the metal ions and the Schiff base compounds is very important for the investigation of the physiology and pharmacology activity of the complexes.This paper describes the category, synthesis and characterization of the Schiff base compounds. 19 Schiff base ligands and 27 novel transition metal complexes have been synthesized and characterized by elemental analysis, IR spectra and X-ray single-crystal diffraction. The role of the self-assembly and influencing factors of the final structures have been summarized. The paper contains four parts:1. 10 CdII and ZnII complexes based on the Schiff base ligands which derived from the condensation of Salicylaldehyde and its derivatives with primary amines have been synthesized and structural characterized.2. Bis-Schiff base ligands have been synthesized based on the condensation of 3-methoxysalicylaldehyde and 3,5-dichlorosalicylaldehyde with 1,3-diaminopropane, respectively. Three novel bis-Schiff base CuII and ZnII complexes have been synthesized and structural characterized.3. Seven mononuclear Schiff base CuII and ZnII complexes have been synthesized from the Schiff base ligands derived from the condensation of Salicylaldehyde and its derivatives with N,N-diethyl-1,2-diaminoethane, N-cyclohexyl-1,3-diaminopropane, etc.4. Seven polynuclear Schiff base CuII and NiII complexes have been synthesized from the Schiff base ligands derived from the condensation of Salicylaldehyde and its derivatives with some primary amines.Based on a series of experimentations, we found that such Schiff base ligands are easily coordinate to the metal complexes, even at room temperature. The bridging groups, such as azide and thiocyanate ligands, conduced to the formation of polynuclear complexes. Moreover, the anions, solvents and proportion of starting materials can influence the structures of the final complexes.