Synthesis, Characterization And Catalytic Activity Of Organoidnthanide Complexes With2-(2,6-dimethylpheiiyliminomethylene)-8-hydroxyquinoiine Ligand

The reaction of8-Hydroxyquinoline-2-aldehyde with2,6-dimethylaniline in a1:1molar ratio in ethanol under refluxing for24hours afforded an2-（2,6-dimethylphenyliminomethylene）-8-hydroxy-quinoline （1）. Treatment of [（Me₃Si）₂N]₃RE（III）（μ-Cl）Li（THF）₃（RE=Dy,Er, Yb, Y） with1equiv of1for12hours in toluene at65°C, afterrecrystallization from hexane, gave novel mononuclear rare-earth metalcomplexes {η¹:η¹:η¹-2-[2,6-（CH₃）₂C₆H₃N=CH]-8-O-C₉H₅N}Y[N（SiMe₃）₂]₂（2） in65%yield;{η¹:η¹:η¹-2-[2,6-（CH₃）₂C₆H₃N=CH]-8-O-C₉H₅N}Y[N（SiMe₃）₂]₂2（3） in68%yield;{η¹:η¹:η¹-2-[2,6-（CH₃）₂C₆H₃N=CH]-8-O-C₉H₅N}Y[N（SiMe₃）₂]₂（4） in58%yield;{η¹:η¹:η¹-2-[2,6-（CH₃）₂C₆H₃N=CH]-8-O-C₉H₅N}Y[N（SiMe₃）₂]₂（5） in55%yield respectively. All the complexes were fully characterized byelemental and spectroscopic analyses. The structures of complexes2,3,4,5were determined by X-ray diffraction.At the same time, we have studied the catalytic activity of the aboverare-earth metal complexes for the guanylation of carbodiimides witharomatic amines. The results showed that all organolanthanide complexes exhibited a high catalytic activity. Moreover, the solvents and catalystloading affected the yield of the reactions. A variety of aromatic amineswere evaluated under the optimized reaction conditions. The resultsindicated that the electronic and steric effects of the substituents havedifferent influence on the outcome of the reactions.