2D-QSPR/DFT studies of aryl-substituted PNP-Cr-based catalyst systems for highly selective ethylene oligomerization
2D-QSPR/DFT studies of aryl-substituted PNP-Cr-based catalyst systems for highly selective ethylene oligomerization
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用于高选择性乙烯齐聚的芳基取代 PNP-Cr 基催化剂体系的 2D-QSPR/DFT 研究
DOI：
10.1007/s00894-014-2129-4
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发表时间：
2014-02
影响因子：
2.2
通讯作者：
Liu, Boping
中科院分区：
文献类型：
--
作者：
Zhan, Xingwen;Cheng, Ruihua;He, Xuelian;Liu, Boping
1-己烯和1-辛烯是合成高性能聚烯烃的重要共聚单体。近年来，N-取代Cr-双（二苯基膦基）胺（PNP-Cr）催化剂在高选择性乙烯三聚/四聚反应中表现出了优异的性能。本文采用基于密度泛函理论（DFT）的二维定量结构-性质关系（QSPR）方法对一系列芳基取代的PNP-Cr催化剂进行了研究。采用启发式方法（HM）和最佳多元线性回归（BMLR）建立了描述选择性与催化剂结构之间关系的最佳线性回归模型。铬（I）和铬（II）的活性位点模型乙烯三聚/四聚。结果表明：（1）自定义的描述子提高了模型的相关性和稳定性：（2）Cr（I）/Cr（III）中心是乙烯三聚反应最可能的活性中心，Cr（II）/Cr（IV）中心是乙烯四聚反应最可能的活性中心; PNP-Cr体系的骨架结构具有良好的平面化和对称性，而PNP-Cr骨架对N原子的空间位阻效应较大，有利于乙烯的三聚。基于描述子分析和最佳线性回归模型，预测了六种新的具有高乙烯三聚/四聚选择性的PNP配体，为进一步开发性能更好的新型催化剂体系提供了良好的基础。图芳基取代的PNP-Cr基催化剂体系
1-Hexene and 1-octene are important comonomers for the synthesis of high performance polyolefins. Recently, various N-substituted Cr-bis(diphenylphosphino)amine (PNP-Cr) catalysts show the potential as excellent candidates for highly selective ethylene trimerization/tetramerization. In this work, a series of aryl-substituted PNP-Cr catalysts were studied by two-dimensional quantitative structure–property relationship (QSPR) method based on density functional theory (DFT) calculations. The heuristic method (HM) and best multi-linear regression (BMLR) were used to establish the best linear regression models to describe the relationship between selectivities and catalyst structures. Both Cr(I) and Cr(II) active site models for ethylene trimerization/tetramerization were considered. It was found that 1) the relativity and stability of the models were increased by using self-defined descriptors based on DFT calculations; 2) Cr(I)/Cr(III) centers were the most plausible active sites for ethylene trimerization, while Cr(II)/Cr(IV) active sites were most possibly responsible for ethylene tetramerization; and 3) the skeleton structures of the PNP-Cr system with good complanation and symmetry were crucial for achieving excellent catalytic selectivity of 1-octene, while the PNP-Cr backbone with a large steric effect on N atom would benefit ethylene trimerization. Six new PNP ligands with high selectivity toward ethylene trimerization/tetramerization were predicted based on descriptor analysis and the best linear regression models providing a good basis for further development of novel catalyst systems with better performance.FigureAryl-substituted PNP-Cr-based catalyst systems
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影响因子：
4.6
作者：
F. Lena;C. Chai
通讯作者：
F. Lena;C. Chai
影响因子：
7.3
作者：
Kuhlmann, Sven;Blann, Kevin;Wasserscheid, Peter
通讯作者：
Wasserscheid, Peter
影响因子：
15
作者：
Overett, MJ;Blann, K;Morgan, DH
通讯作者：
Morgan, DH
影响因子：
4.9
作者：
Carter, A;Cohen, SA;Wass, DF
通讯作者：
Wass, DF
DOI：
10.1007/978-3-642-16729-4
发表时间：
2011-01
期刊：
Advanced Materials Research
影响因子：
--
作者：
R. Mart;G. Reinelt
通讯作者：
R. Mart;G. Reinelt