| Reaction of acetone with 1 equiv of pyrrole in anhydrous ethanol yielded (C4H2NH)4[C(CH3)2]4 (1) in 75% yield. Treatment of [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3 (Ln = Sm, Nd, Dy) with 1/2 equiv of 1 in toluene under refluxing for 48 hours, after recrystallization from hexane, gave novel nine coordinate and dinuclear rare-earth metal complexes {(η1-C4H2N)[C(CH3)2]2(η5-C4 H2N) Sm[N(SiMe3)2]}2 (2) in 72% yield; {(η1-C4H2N)[C(CH3)2]2(η5-C4H2N) Nd[N(SiMe3)2]}2 (3) in 65% yield; {(η1-C4H2N)[C(CH3)2]2 (η5-C4H2N) Dy[N(SiMe3)2]}2 (4) in 58% yield, respectively. All the complexes were fully characterized by elemental and spectroscopic analyses. The structures of complexes 2, 3, 4 were determined by X-ray diffraction.At the same time, We have studied the catalytic activity of the above organolanthanide complexes as single-componentε-caprolactone and L-LA polymerization catalysts. The results show that the changes of central metal ions, the solvents, temperatures, the mole ratio of catalyst to the monomer, the volume ratio of monomer and solvent have influences on activities of catalysts,molecular weight of polymer and the molecular weight distribution.
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