有机化学 ›› 2018, Vol. 38 ›› Issue (8): 2151-2160.DOI: 10.6023/cjoc201803035 上一篇    下一篇

所属专题: 元素有机化学合辑2018-2019

研究简报

杂环膦亚胺钛配合物的合成及催化乙烯聚合

王铁石a, 陈建军b, 叶霖a,c, 张爱英a,c, 冯增国a,c   

  1. a 北京理工大学材料学院 北京 100081;
    b 中国石油化工股份有限公司北京北化院燕山分院 北京 102500;
    c 北京市结构可控先进功能材料与绿色应用重点实验室 北京 100081
  • 收稿日期:2018-03-23 修回日期:2018-04-25 发布日期:2018-05-03
  • 通讯作者: 冯增国 E-mail:sainfeng@bit.edu.cn
  • 基金资助:

    中国石油化工股份有限公司技术开发(No.214002)资助项目.

Synthesis of Titanium Heteroarylphosphinimine Complexes and Application for Ethylene Polymerization

Wang Tieshia, Chen Jianjunb, Ye Lina,c, Zhang Aiyinga,c, Feng Zengguoa,c   

  1. a School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081;
    b Sinopec Yanshan Branch, Beijing Research Institute of Chemical Industry, Beijing 102500;
    c Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, Beijing 100081
  • Received:2018-03-23 Revised:2018-04-25 Published:2018-05-03
  • Contact: 10.6023/cjoc201803035 E-mail:sainfeng@bit.edu.cn
  • Supported by:

    Project supported by the Technology Development Project of China Petroleum & Chemical Corporation (Sinopec) (No. 214002).

首先合成单取代和双取代杂环膦化合物R-PPh2[R=2-吡啶基(3a),2-噻吩基(3b),2-呋喃基(3c)]和Ph2P-R'-PPh2[R'=2,6-吡啶基(6a),2,5-噻吩基(6b),2,5-呋喃基(6c)].然后与叠氮三甲基硅烷发生Staudinger反应生成相应的杂环膦亚胺配体R-PPh2(NSiMe3)和(Me3SiN)Ph2P-R'-PPh2(NSiMe3).最后与环戊二烯三氯化钛反应脱去三甲基氯硅烷后得到具有烯烃聚合催化活性的杂环膦亚胺钛配合物.所有配合物结构都经过核磁的确认,为了进一步确定配合物分子结构,利用单晶X射线衍射解析了所有钛配合物的晶体结构.在助催化剂甲基铝氧烷(MAO)活化作用下,双钛中心配合物6a~6c比单钛中心类似配合物3a~3c表现出更高的催化乙烯聚合活性,所得聚合物具有较宽分子量分布呈双峰分布,6b在较低聚合温度下就可以制备超高分子量聚乙烯.

关键词: 双金属钛配合物, 杂环基团, 膦亚胺, 乙烯聚合

Mono-and bisdiphenyl substituted heteroarylphosphines R-PPh2[R=2-pyridyl (3a), 2-thienyl (3b) and 2-furyl (3c)] and Ph2P-R'-PPh2[R'=2,6-pyridyl (6a), 2,5-thienyl (6b) and 2,5-furyl (6c)] were synthesized. After Staudinger reaction with Me3SiN3, those heteroarylphosphines were converted into the heteroarylphosphinimine ligands, R-PPh2(NSiMe3) and (Me3SiN)Ph2P-R"-PPh2(NSiMe3). The subsequently dehalosilylation reaction with CpTiCl3 afforded the corresponding Ti heteroarylphosphinimine halfmetallocenes as olefin polymerization catalysts. The structures of all the complexes were determined by means of 1H NMR, 13C NMR and 31P NMR spectroscopic methods and further confirmed by single-crystal X-ray diffraction analysis. When activated with methylaluminoxane (MAO) at a ratio of Al/Ti=600 and under 0.5 MPa of ethylene, these bimetallic Ti phosphinimine complexes displayed a higher catalytic activity compared to the monometallic analogues, but resulted in polymers with bimodal molecular weight distributions. Unexpectedly, 6b produced ultrahigh Mw polyethylene at lower polymerization temperature.

Key words: bimetallic titanium catalyst, heteroaryl, phosphinimine, ethylene polymerization