论文部分内容阅读
Discrete ion-pair complexes [Ln(EDBP)2(DME)Na(DME)3] [Ln=Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2,2’-ethylidene-bis(4,6-di-tert-butylphenol)(EDBPH2) and Ln(BH4)3·3THF (Ln=Er, Yb, Sm) followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1―3 can all be used as single component initiators for the ring-opening polymerization of ε-caprolactone.
Discrete ion-pair complexes [Ln (EDBP) 2 (DME) Na (DME) 3] [Ln = Er (1), Yb (2), Sm (3)] have been synthesized by the reaction between sodium salt of 2, 2’-ethylidene-bis (4,6-di-tert-butylphenol) (EDBPH2) and Ln (BH4) 3.3THF (Ln = Er, Yb, Sm) were followed by centrifugation and recrystalization. The complexes were characterized by elemental analysis and FT-IR, and the bonding model of these compounds was confirmed by X-ray single crystal diffraction for complex 1. It was found that four O atoms in two biphenol ligands as well as two O atoms in one ethylene glycol dimethyl ether (DME ) molecule connect to the center rare earth metal atom, while sodium exists as counterpart cation to balance the charge. Complexes 1-3 can all be used as single component initiators for the ring-opening polymerization of ε-caprolactone.