Studies On Rare Earth Complexes Supported By Pyrrolyl Bridged Multidentate Ligand Containing Nitrogen Atoms:Syntheses,Structures And Catalytic Activity

In this thesis,the N,N,N,N,N-type pyrrole bridged multidentate ligand 2,5-{[CH3N(CH2CH2)N]CH2}2C4H3NH(1)were synthesized by Mannich reaction of pyrrole,formaldehyde,N-methyl piperazine.Reactivity of 2,5-difunctional pyrroly ligand 1 with rare earth amine complexes [(Me3Si)2N]3RE(?-Cl)Li(THF)3 afforded a serials of rare earth complexes bearing amide and chloride with formula as [?1:?1:?1:?1-2,5-{[CH3N(CH2CH2)2N]CH2}2C4H3N]RECl[N(SiMe3)2](RE = Sm(2),Dy(3),Er(4),Y(5),Yb(6))in high yields.Reactivity of 2,5-difunctional pyrroly ligand 1 with rare earth alkyl complexes RE(CH2SiMe3)3(THF)2 gave a serials of rare earth bisalkyl complexes [?1:?1:?1:?1-2,5-{[CH3N(CH2CH2)N]CH2}2C4H3N]RE(CH2SiMe3)2(RE = Dy(7),Er(8),Y(9),Yb(10)).All complexes were fully characterized by elemental analys is and IR,their structures were furtherly determined by single-crystal X-ray diffraction study.The catalytic system of complexes 7-10 as catalysts,alkyl aluminum(AlR3)and organic [Ph3C][B(C6F5)4] as cocatalyst,for isoprene polymerization were investigated.Results show that the above catalyst have high catalytic activities with the moderate selectivities.