Synthesis, Characterization And Catalytic Performances Of Fluoro-substituted β-ketoamino And β-diiminato Copper Complexes

In this thesis three series of copper complexes were designed and synthesized,in which there are two sorts of mononuclear copper complexes with fluro-substitutedβ-ketoiminate or β-ketiminate ligands and a kind of dinuclear copper complexes withxylylene-bridged bis(β-ketoiminate) ligands. All these copper complexes werecharacterized by FT IR and elemental analysis. Further more, six copper complexeswith β-ketoiminate or β-ketiminate ligands were further tested by XRD. The resultsshowed that the β-ketoamino copper complexes have two trans-β-ketiminate ligandsand form two six-membered rings. Moreover, the copper complexes with one orthosubstitutent on aromatic ring of ligands adopted symmetrical square planar structurewith copper as the center, while the complex with two ortho-fluro substitutentsformed distorted square planar structure with the dihedral angle of28.2o. The coppercomplexes with β-ketiminate and carboxyl ligands took the slightly distorted squareplanar structure. A six-membered ring and a four-membered ones were formed withcopper and β-ketiminate or carboxyl group, and more, all the double bonds of C=Cand C=N on β-ketiminate and C=O on carboxyl group were delocalized to form twoconjugated big π-bonds.The catalytic behaviors of the three series of copper complexes on methylacrylate polymerization were researched in detail. Activated by MMAO, the threetypes of copper complexes can polymerize MA effectively, and the numbers of flurosubstituents on ligands exerted very important effects on catalytic activities, i.e., thestrong electron-withdrawing effects of fluro substituents can improve evidently thecatalytic activities. More fluro atoms existed on ligands, higher activities wouldappear. Further more, the mononuclear copper complexes having the same amouts offluro atoms on β-ketoiminate or β-ketiminate ligands owned the similar activities.However, the dinuclear copper complexes with xylylene-bridged bis(β-ketoiminate)ligands had higher activities, better thermal stability and less usage of MMAO thanthe corresponding β-ketoiminate ligated mononuclear ones.The polymerization of methyl methacrylate catalyzed by mononuclear anddinulear copper complexes with β-ketoiminate or bridged bis(β-ketoiminate) ligandswas investigated. These complexes can catalyze the polymerization of MMAeffectively to produce syndio-rich atactic polymers with strong electron-withdrawingeffects of fluro substituents. Similarly, stronger electron-withdrawing effects wouldbring higher catalytic activities. The syndiotacticity of polymers can reach75%.The copolymerization of MA and1-hexene with β-ketoiminate or β-ketiminate ligated copper complexes activated with MMAO was studied and MA-richcopolymers were obtained. The ortho fluro substitutents on aromatic ring of ligandscan increase the catalytic activities, while the meta or para fluro substitutents woulddecrease the activities. β-Ketiminate ligated copper complexes with bromo anion hadhigher catalytic activities than with other anions. The contents of1-hexene incopolymers can reach18%.