Quantitatively Study on Catalytic Activities of Transition Metal Complexes in Ethylene Oligo/Polymerization
The activities for transition metal complex precatalysts towards ethylene polymerization have been studying in our recent works.First, from the electronic effect view, the density functional theory combined with QEq method was performed to investigate the polymerization activity through a quantitative correlation with net charges on central metal.1a-1c Besides, the HOMO-LUMO energy gaps and the energy difference among the various spin state also have certain correlation with catalytic activities.1d Then using multiple linear regression analysis the reaction activities were predicted from both electronic and steric effect for arylimino-pyridine based transition metal complexes (Fe, Cr, Co) in ethylene polymerization.The obtained results present very good correlations with the R2 values ranged from 0.93 to 1.0.On the basis of the results, the electronic effect is dominant in determining the catalytic activity for Fe and Co complexes, while for Cr complexes it is steric effect.le Finally, the quantitative structure-activity relationship (QSAR) approach was used to investigate the catalytic activities for a date set of 58 2-azacyclyl-6-aryliminopyridyl complex analogues with different transition metals (Fe, Co, Ni,and Cr).1f The final QSAR model containing 18 descriptors showed good predictability for training set (R2 =0.913, Q2 =0.873) and test set (Rt2 =0.971).Furthermore, 20 new complexes were designed based on the obtained QSAR model.Most of the designed complexes were calculated to show higher activities,indicating that the present QSAR modeling results have the potential to be a viable method to predict and design transition metal complex catalysts with high activity.
Wenhong Yang Wen-Hua Sun
Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
国际会议
9th International Symposium on High-Tech Polymer Materials(第9届国际高技术高分子材料学术会议)(HTPM-9)
郑州
英文
28-28
2016-07-11（万方平台首次上网日期，不代表论文的发表时间）