No abstract

No abstract

No abstract

Reaction of DyCl3 with two equivalents of NaN(SiMe3)2 in THF yielded {Dy(μ‐Cl)[N(SiMe3)2]2(THF)}2 (1). X‐ray crystal structure analysis revealed that 1 is a centrosymmetric dimer with asymmetrically bridging chloride ligands. The metal coordination arrangement can be best described as distorted trigonal bipyramid. The bond lengths of Ln–Cl and Ln–N showed a decreasing trend with the contraction of the size of Ln3+. Treatment of N,N‐bis(pyrrolyl‐α‐methyl)‐N‐methylamine (H2dpma) with 1 and known compound {Yb(μ‐Cl)[N(SiMe3)2]2(THF)}2, respectively, led to the formations of [Dy(μ‐Cl)(dpma)(THF)2]2 (2) and {Yb(μ‐Cl)[N(SiMe3)2]2(THF)}2 (3). Compounds 2 and 3 were fully characterized by single‐crystal X‐ray crystallography, elemental analysis, and 1H NMR spectroscopy. Structure determination indicated that 2 and 3 exhibit as centrosymmetric dimers with asymmetrically bridging chloride ligands. One pot reactions involving LnCl3 (Ln = Dy and Yb), LiN(SiMe3)2, and H2dpma were explored and desired products 2 and 3 were not yielded, which indicated that 1 and {Yb(μ‐Cl)[N(SiMe3)2]2(THF)}2 are the demanding precursors to synthesize Dysprosium and Ytterbium complexes supported by dpma2– ligand. Compounds 2 and 3 are the first reported lanthanide complexes chelated by dpma2– ligand.

The synthesis, structures and catalytic activities of three organolanthanide complexes supported by the H 3 tpa ligand (H 3 tpa = tris(pyrrolyl-α-methyl) amine) are described. Treatment of H 3 tpa with one equivalent of Ln[N(SiMe 3 ) 2 ] 3 (Ln = Sc, Sm, Dy) in THF gives, after recrystallization from toluene/THF solution, Sc(tpa)(THF) 2 (1), 117 Sm(tpa)(THF) 3 (2) and Dy(tpa)(THF) 3 (3) in good yields. The structures of complexes 1-3 were determined by single-crystal X-ray diffraction and elemental analysis. Complexes 2 and 3 exhibited good catalytic activity for the polymerization of ε-caprolactone.