Chinese Science Bulletin

, 54:3795 | Cite as

Synthesis and characterization of N-aryloxo-functionalized β-ketoiminate rare-earth complexes and their catalytic activity for the polymerization of ɛ-caprolactone

  • XiangZong Han
  • LiangLiang Wu
  • YingMing Yao
  • Yong Zhang
  • Qi Shen
Articles / Inorganic Chemistry
First Online:
Received:
Accepted:

Abstract

The synthesis and characterization of dimeric rare-earth amides stabilized by a dianionic N-aryloxo functionalized β-ketoiminate ligand are described. Reactions of 4-(2-hydroxy-5-methyl-phenyl) imino-2-pentanone (LH2) with Ln[N(SiMe3)2]3(μ-Cl)Li(THF)3 in a 1:1 molar ratio in THF gave the dimeric rare-earth amido complexes [LLn{N(SiMe3)2}(THF)]2 [Ln = Nd (1), Sm (2), Yb (3), Y (4)]. These complexes were well characterized, and the definitive molecular structures of complexes 3 and 4 were determined. It was found that complexes 1–4 can initiate the ring-opening polymerization of ɛ-caprolactone, and the ionic radii of the central metals have significant effect on the catalytic activity.

Keywords

rare earth β-ketoiminate ligand amide synthesis polymerization ɛ-caprolactone 
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Copyright information

© Science in China Press and Springer-Verlag GmbH 2009

Authors and Affiliations

  • XiangZong Han
    • 1
  • LiangLiang Wu
    • 1
  • YingMing Yao
    • 1
  • Yong Zhang
    • 1
  • Qi Shen
    • 1
  1. 1.Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Dushu Lake CampusSoochow UniversitySuzhouChina

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