| Reaction of pyrrole with 1 equiv of cyclohexanone in Et2OH at room temperature yielded (C4H2NH)4[C(C5H10)2]4 (1) in 95% yield. Treatment of 2 equiv of [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3 (Ln = Sm, Nd) with 1 equiv of 1 in toluene under refluxing for 24 hours, after recrystallization from hexane, gave novel nine coordinate and dual-core rare-earth metal complexes, {(η1-C4H2N)C(C5H10)2(η5-C4H2N)SmN(SiMe3)2}2 (2) in 83% yield; {(η1-C4H2N)C(C5H10)2(η5-C4H2N)NdN(SiMe3)2}2 (3) in 69% yield, respectively. All the complexes were fully characterized by elemental and spectroscopic analyses. The structures of complexes 2, 3, were determined by X-ray diffraction.At the same time, We have studied the catalytic activity of the above organolanthanide complexes as single-component polymerization catalysts ofε-caprolactone and L-Lactide. The results show that the changes of central metal ions, temperatures, the solvents, the mole ratio of catalyst and 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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