Study on synthesis and characterization of a novel pyridine imide ligated rare earth metal complex C₂₈H₅₁N₂Ln (THF)_n(CH₂SiMe₃)₃(Ln = Sc, Y) and its catalytic performance in polymerization of isoprene

We simply synthesized the pyridine imine rare earth trialkyl Figures (2, 3) by using the isofold scandium trialkyl complex Sc3(THF)2.5(CH2SiMe3) and the Yttrium trialkyl complex Y(THF)2.5(CH2SiMe3)3 with the pyridine imine derivative ligand (1: C28H51N2Sc (THF) (CH2SiMe3)3; 2: C28H51N2Y(THF)0.625(CH2SiMe3)3. In situ, nuclear magnetic resonance (NMR) showed that for pyridine imine rare earth trialkyl Figures (2, 3), different feed ratios of borate [Ph3C] [B(C6F5)4] to catalyst and different feed sequences of borate and alkyl aluminum can produce different catalytic active species. These catalytic active species can realize high activity (4.08 × 104g·molSc-1·h-1), high selectivity, and narrow molecular weight distribution (1.4) polymerization of conjugated diene such as isoprene.