title: Carbon bridged triphenolate lanthanide complexes: synthesis, characterization, DFT studies and catalytic activities for isoprene polymerization.
abstract: The dinuclear lanthanide complexes [Ln2(L)2(THF)n] (Ln = Nd (1) n = 4, Gd (2) n = 3, Lu (3) n = 2) supported by carbon bridged triphenolate ligands [LH3 = tris(3,5-di-tert-butyl-2-hydroxyphenyl)methane] were synthesized via a salt metathesis reaction between lanthanide trichlorides and LNa3 in THF. All complexes were characterized by elemental analysis and X-ray crystallography, and complex 3 was characterized by (1)H and (13)C NMR spectroscopy. Agostic interactions were found in these complexes and were further substantiated by DFT calculations of complex 3. These lanthanide complexes in combination with aluminum alkyls and [Ph3C](+)[B(C6F5)4](-) generated efficient homogeneous catalysts for the cis-1,4 polymerization of isoprene, with complex 1 having the best catalytic activity.
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China. xufengni@zju.edu.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Liang
authors.forename: Jun
authors.initials: J
authors.lastname: Ling
authors.forename: Xufeng
authors.initials: X
authors.lastname: Ni
authors.forename: Zhiquan
authors.initials: Z
authors.lastname: Shen