吲哚基NCN钳型钛族金属配合物的合成及其催化苯乙烯聚合反应
Indolyl-based NCN-pincer titanium group metal complexes:Synthesis and catalytic application for styrene polymerization
刘欢欢 1童尧 1黄江胜 1王芬华1
作者信息
- 1. 安徽工程大学化学与环境工程学院,芜湖 241000
- 折叠
摘要
以吲哚为骨架,在吲哚的1位、3位引入2条边臂基团得到了 1,3-双取代吲哚基化合物,用丁基锂去质子后与MCl4(M=Ti、Zr、Hf)反应,得到一系列NCN钳型钛、锆、铪金属配合物(3-Ti、3-Zr、3-Hf).该系列配合物通过核磁、元素分析及单晶X射线衍射进行了表征.单晶结构显示,金属中心除与3个氯原子配位外,还与配体以κ3NCN的形式配位,形成六配位的八面体构型.考察了该类型配合物在不同助催化体系条件下催化苯乙烯聚合反应的性能.实验发现:在室温下,助催化剂为AlEt2Cl/(Ph3C)[B(C6F5)4],甲苯为溶剂,单体与催化剂在浓度比300∶1的条件下,不同金属中心配合物都能以高转化率得到聚苯乙烯,其中铪配合物的催化活性最高.催化所得的聚苯乙烯经表征发现均为无规结构,数均分子量为4 000～8 000.
Abstract
Indole worked as the backbone and two side arms at the 1-,and 3-positions were introduced to obtain a 1,3-di-functionalized indolyl compound.After the deprotonation by BuLi,it was reacted with MCl4(M=Ti,Zr,Hf)to form a series of NCN-pincer type titanium group metal complexes(3-Ti,3-Zr,3-Hf).The complexes were character-ized by NMR,elemental analysis,and single-crystal X-ray diffraction.The single-crystal structures revealed that the metal center bonds with the ligand in κ3 NCN modes and three chlorine atoms to form a six-coordinated distorted octa-hedral configuration.Styrene polymerization was investigated with 3-Ti,3-Zr,and 3-Hf using aluminum alkyls and borate reagents as cocatalysts when the concentration ratio of the monomer to the complex was 300∶1.It was found the complexes of different metal centers could efficiently catalyze styrene polymerization with high conversion under room temperature and using AlEt2Cl/(Ph3C)[B(C6F5)4]as cocatalysts,moreover,the hafnium complex displayed the higher activity.The obtained polystyrene was characterized by gel permeation chromatography(GPC)and 13C NMR.The results showed the polymer was atactic and had a low number-average molecular weight(Mn=4 000-8 000).CCDC:2332412,3-Ti;2332412,3-Zr;2332414,3-Hf.
关键词
亚氨基吲哚/NCN钳型/钛族金属配合物/苯乙烯/聚合Key words
imino substituted indole/NCN-pincer type/titanium group metal complex/styrene/polymerization引用本文复制引用
基金项目
安徽省教育厅项目(GXXT-2021-052)
安徽工程大学人才培育科研启动基金()
出版年
2024
NETL
NSTL
万方数据