取代基对希夫碱钼配合物催化烯烃环氧化反应的影响

Substituent Effect on the Epoxidation of Olefins Catalyzed by Schiff Base Molybdenum Complexes

变换苯甲醛环5位置上的氯取代基和苯胺环5’位置上的硝基制备了4种希夫碱钼配合物催化剂,在不使用有机溶剂的条件下催化环辛烯水相环氧化反应,考察了它们的催化活性,发现:引入吸电基可提高希夫碱钼配合物的催化性能,在优化的催化剂(0.1%)上环辛烯转化率达到了94%,环氧化物选择性均大于88%。反应体系简单、经济、清洁。

The 5-position of Cl on benzaldehyde ring and 5’-position of NO_(2)on aniline ring were brought to the backbone of the ligands to prepare four different Schiff base molybdenum complexes,and their catalytic performances in the catalytic epoxidation of cyclooctene under solvent-free condition were investigated.It is found that the introduction of electron withdrawing group has an obvious effluence on the catalytic process,and the conversion of cyclooctene reaches up to 94%over the optimal catalyst(0.1%)with high epoxide selectivity(>88%).Furthermore,the catalytic system is simple,economic and clean.