Abstract: Polyethylene glycol-400（PEG-400）grafted in silica（SiO₂）support as macromolecule ligand was synthesized, and the structure of the ligand was characterized by IR spectroscopy.The complex of silica-supported PEG-400 and molybdenum(Ⅵ)dioxo(2,4-pentanedione)［shortened form,SiO₂-PEG-Mo(Ⅵ)］was for the first time synthesized and characterized by infrared spectroscopy.The possible structure of the complex was discussed.As a catalyst, SiO₂-PEG-Mo(Ⅵ)complex was used in epoxidation process of cyclohexene,and its catalytic activity and selectivity was also investigated.Experimental results showed that the complex possessed excellent activity and selectivity for epoxidation of cyclohexene.A new analysis method of the amount of Mo in the catalyst and the analysis of epoxycyclohexane by gas chromatography were set up.For n(t-BuOOH) = 0.1 mol,n(cyclohexene)∶n(t-BuOOH)=3.5∶1,the volume of solvent was about 10 ml, reaction temperature 80 ℃,reaction time 60 min，and the amount of SiO₂-PEG-Mo(Ⅵ)complex catalyst was 0.5 g.In this reaction condition, based on t-BuOOH,the yield of epoxycyclohexane was more than 99.2%,the purity of epoxycyclohexan was about 99.5% by GC analysis.The catalyst recycled for 3 times still possessed high catalytic activity and selectivity,and the yield of cyclohexene oxide approached 99% in the above-mentioned reaction condition.

Key words: 钼（Ⅵ）配合物, 环己烯, 环氧环己烷, 聚乙二醇, SiO₂

摘要： 合成了SiO₂键合聚乙二醇（PEG）高分子配体，将钼（Ⅵ）合乙酰丙酮组装在该高分子配体上合成出SiO₂负载PEG钼（Ⅵ）配合物，并用元素分析、红外光谱以及X射线光电子能谱技术对其进行了结构表征.建立了SiO₂键合PEG钼（Ⅵ）配合物催化剂中Mo的化学分析新方法.实验表明：该配合物作为环己烯环氧化用催化剂，具有优良的催化活性和选择性.在叔丁基过氧化氢为0.1 mol、环己烯与叔丁基过氧化氢摩尔比为3.5∶1、溶剂10 ml、反应温度80 ℃、时间60 min条件下，环氧环己烷收率（以叔丁基过氧化氢计）在99.2%以上，质量分数≥99.5%（GC检测）.

关键词: 钼（Ⅵ）配合物, 环己烯, 环氧环己烷, 聚乙二醇, SiO₂