MCM-41固载Co席夫碱配合物的制备及其催化烯烃环氧化的研究

环氧化合物作为有机合成中间体具有广泛应用,催化烯烃环氧化一直是催化化学中的一个重要课题1～2].尽管已经报道了以过酸、过氧化氢、烷基过氧化物、或分子氧为氧化剂,以金属配合物(通常为钌、钼、钛的配合物)为催化剂的反应体系,但对环氧化物的选择性却很低3].另外,除了需探索具有高选择性的催化体系外,应用分子氧或空气作为氧化剂更适宜于经济和安全的要求.目前,在以分子氧作为氧化剂,均相催化烯烃环氧化的研究中,应用醛类化合物作为氧转移试剂是一种有效的和方便的促进烯烃环氧化的方法4].但是,均相催化剂难于分离和重复使用,因此…

Study on Preparation of Co Schiff Base Complex Immobilized in MCM-41 and Its Catalytic Performance for Alkenes Epoxidation

Preparation of Co schiff base complex immobilized on MCM\|41 by the 3\|aminopropyltriethoxysilane modified mesoporous molecular sieve MCM\|41 reacted with cobalt nitrate and salicylaldehyde. Such cobalt schiff base complex immobilized on MCM\|41 could be used as the catalyst, with O\-2 as the oxidant and isobutyraldehyde as the sacrificial reagent, to catalyze the epoxidation of cyclohexene and styrene in CH3CN. After 4h of reaction, the conversion of cyclohexene reached 98% and the selectivity to epoxy cyclohexane, 88%; the conversion of styrene reached 89% and the selectivity, 69%. In addition, the catalyst could remain its catalytic activity after several reuses.