枝状钴配合物的合成及其对苯乙烯环氧化的催化性能

Synthesis of dendritic cobalt(Ⅱ) complex and catalytic performance for epoxidation of styrene

将合成的配体4-(2-吡啶甲醛亚氨基)苯酚与醋酸钴反应得到钴(Ⅱ)配合物(CoL),再将CoL负载到碳硅烷枝状分子上,制备成枝状钴(Ⅱ)配合物催化剂(CS-CoL),并通过傅里叶红外光谱(FT-IR)、元素分析、氢谱(1H NMR)等对相关化合物进行表征。以分子氧为氧源,将催化剂用于催化苯乙烯的环氧化反应,同时考察催化剂的种类、溶剂、反应温度和反应时间对苯乙烯环氧化反应性能的影响。结果表明:负载后的枝状催化剂CS-CoL比单体催化剂CoL的催化活性高,苯乙烯的转化率为99.9%,环氧苯乙烷的选择性达59.5%,同时也说明枝状载体具有正向的"枝状分子效应"。

The synthesized ligand 4-[ （2-pyridinylmethylene） amino] phenol reacted with cobalt（ II ） acetate to give the cobalt（ II ） complex（CoL） ,then the CoL was further anchored on carbosilane dendrimer to obtain the dendritic cobalt （II） complex catalyst （ CS-CoL）.The related compounds were characterized by Fourier transform infrared spectroscopy （FT-IR）, elemental analysis and hydrogen nuclear magnetic resonance spectroscopy（ 1H NMR）.The catalyst was evaluated for the epoxidation of styrene with 02 as oxidant. And the effects of reaction conditions of catalyst, solvent, reaction temperature, and reaction time, were further investigated.For epoxidation of styene with Oz ,the immobilized cobalt（II） complex was more effective than monomer cobalt（II） complex with styrene conversion of 99. 9% and epoxide selectivity of 59. 5%.Dendritic molecule carriers had a positive effect of dendritic molecules on epoxidation of styrene.