Synthesis, characterization and 1,3-butadiene polymerization studies of cobalt dichloride complexes bearing pyridine bisoxazoline ligands
作者:Jun Guo、Baolin Wang、Jifu Bi、Chunyu Zhang、Hexin Zhang、Chenxi Bai、Yanming Hu、Xuequan Zhang
DOI:10.1016/j.polymer.2015.01.006
日期:2015.2
of [CoL2]2+ can be described as distorted octahedron. In combination with ethylaluminum sesquichloride, these cobalt complexes displayed high catalytic activity and cis-1,4-selectivity towards 1,3-butadiene polymerization. The selectivity of the catalytic system can be tuned to predominantly 1,2-fashion via addition of PPh3. The effects of reaction parameters and the ligand environment on the polymerization
成功地合成了一系列带有吡啶双恶唑啉配体的离子对钴配合物,并通过红外光谱和元素分析对其进行了表征。通过X射线晶体学分析确定,络合物4a,4b,4e和4f作为由[CoL 2 ] 2+和[CoCl 4 ] 2-组成的离子对存在。在该络合物中,钴原子被两个配体的六个氮原子配位,并且其配位几何在[CoL 2 ] 2+的钴中心可以形容为扭曲的八面体。与乙基倍半氯化铝结合使用时,这些钴配合物显示出较高的催化活性和对1,3-丁二烯聚合的顺式-1,4-选择性。催化体系的选择性可以通过添加PPh 3调整为1,2-方式。还研究了反应参数和配体环境对聚合反应的影响。