Synthesis and characterization of bis(guanidinate)lanthanide diisopropylamido complexes
作者:Yingming Yao、Yunjie Luo、Jinglei Chen、Zhenqin Zhang、Yong Zhang、Qi Shen
DOI:10.1016/s0022-328x(03)00600-4
日期:2003.8
Treatment of LnCl(3) with [(SiMe3)(2)NC(NiPr)(2)]Li in 1:2 molar ratio afforded the soluble bis(guanidinate)lanthanide chlorides [(SiMe3)(2)NC(NiPr)(2)](2)Ln(mu-Cl)}(2) (Ln=Y (1), Nd (2)). Amination of 1 and 2 with two equivalents of LiN(iPr)(2) in a mixture solution of toluene and hexane gave [(SiMe3)(2)NC(NiPr)(2)](2)LnN(iPr)(2) (Ln -Y (3), Nd (4)) in good isolated yields. The single-crystal structural analyses of 2 and 3 revealed that the coordination geometries of lanthanide metals are best described as a distorted pseudo-octahedron and a pseudo-pyramid, respectively. Complexes 3 and 4 exhibited extremely high activity for the polymerizations of epsilon-caprolactone and methyl methacrylate (MMA). (C) 2003 Elsevier B.V. All rights reserved.