摘要
通过肽键作用将Salen型金属配合物接枝到介孔硅胶孔道中生成固相催化剂,采用红外光谱、热重分析和元素分析等对制备的固相催化剂进行表征,结果证实,Salen型金属配合物成功接枝到介孔硅胶载体上。以环辛烯和环己烯为反应底物,叔丁基过氧化氢和过氧化氢为氧化剂,比较均相Salen型催化剂和多相Salen型催化剂的催化活性。制备的均相Salen型催化剂和利用肽键键合制备的固相催化剂均具有一定的催化性能,Mo-Salen催化活性更高,是因为叔丁基过氧化氢在Mo-Salen存在下易分解。固相催化剂活性≤75℃时稳定,在氧化剂叔丁基过氧化氢和过氧化氢作用下具有较好的稳定性能。重复实验中,金属离子流失量很小,催化活性和TOF值未降低,表明利用肽键制备的固相催化剂催化活性稳定,为固相催化剂的制备开辟新思路。
The metal Salen complexes were immobilized on the organo-modified silica framework by peptide bond interactions. The immobilized Salen complexes were characterized by FT-IR, TG-DTA and elemental analysis. The results confirmed that salen-Mn（ Ⅲ） and Salen-Mo（ Ⅳ） complexes were attached to the silica framework. Using tert-butyl hydroperoxide and hydrogen peroxide as the oxidants, the catalytic performance of homogeneous catalysts and immobilized catalysts for catalytic epoxidation of cyclooctene and cyclohexene were studied. The homogeneous and immobilized Mo-Salen complexes exhibited higher catalytic activity for the epoxidation,whereas Mn-Salen complex systems caused additionally non-productive decomposition of tert-butyl hydroperoxide. The immobilized catalysts had good and stable activity below 75 ~C and in the existence of tert-butyl hydroperoxide and hydrogen peroxide. In repeated experiments, the immobilized Salen complex was resistant to leaching of Salen molecule, and its catalytic activity and TOF did not reduce,which indicated that the immobilized catalysts had stabe catalytic activity.
出处
《工业催化》
CAS
2015年第10期767-772,共6页
Industrial Catalysis
基金
湖南省教育厅基金资助项目(13C0455
14C0132)
湖南省教育厅课题(12C0488)
