with four spiro has Calix [4] pyrrole amine ligand binuclear rare earth metal compounds

Title: with four spiro has Calix [4] pyrrole amine ligand binuclear rare earth metal compounds of the synthesis, characterization and catalytic activity of Author: red Degree-granting units: Anhui Normal University Keywords: trivalent rare-earth organic amine compounds;; ligand;; catalysis;; polymerization Summary:

At room temperature, with a new steam rare earth magnets of freshly distilled pyrrole and 1 equivalent of cyclohexanone in the reaction in ethanol, 95% yield to give compound (C_4H_2NH) _4 [C (C_5H_ (10)) _2] _4 (1), with two equivalents of [(Me_3Si) _2N] _3Ln (μ-Cl) Li (THF) _3 (Ln = Sm, Nd,) and 1 equivalent of compound 1 in refluxing toluene for 24 hours, by weight of n-hexane crystals were 83% yield has been nine-coordinated trivalent dual-core new rare earth complexes {(η ~ 1-C_4H_2N) C (C_5H_ (10)) _2 (η ~ 5-C_4H_2N) SmN (SiMe_3) _2} _2 (2) to obtain 69% yield of rare earth complexes {(η ~ 1-C_4H_2N) C (C_5H_ (10)) _2 (η ~ 5-C_4H_2N) NdN (SiMe_3) _2} _2 (3), the compounds were characterized by elemental analysis and spectral. Compounds 2,3 further by X-ray diffraction to determine its crystal structure.

We use the rare earth complexes as catalysts studied as a single-component catalyst caprolactone (ε-CL), L-lactide (L-LA) polymerization activity. The results show that changes in the central metal atom catalyst, solvent, temperature, catalyst and monomer molar http://www.chinamagnets.biz/ ratio and volume ratio of monomer and solvent changes, in both the polymerization activity, polymer molecular weight and molecular weight distribution impact. We optimized the conditions and made possible reaction mechanism Degree Year: 2010