非均相Schiff碱铬(Ⅲ)配合物催化环己烯环氧化性能的研究

摘要

将3种典型的氨基酸-水杨醛Schiff碱铬(III)配合物固载于介孔MCM-41上,制得非均相Schiff碱铬配合物,用傅里叶变换红外光谱、紫外-可见光谱、X射线固体粉末衍射、N2吸附和元素分析对其结构进行了表征,并以30％H2O2为氧化剂,考察该配合物对环己烯环氧化反应的催化性能.结果表明,均相配合物非均相化后,其催化活性明显提高.在较优的反应条件下,环己烯转化率可达52.6％,环氧环己烷选择性为73.5％,且该非均相催化剂重复使用6次后,仍保持较高的催化活性.%Three typical amino acid Schiff base chromium(III) complexes immobilized on MCM-41 were prepared and characterized by various physico-chemical methods such as Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, X-ray powder diffraction, N2 sorption, and elemental analysis. The obtained immobilized complexes were effective catalysts for the epoxidation of cyclohexene with 30% hydrogen peroxide and they exhibited significantly enhanced catalytic performance compared with their corresponding homogeneous analogues. Under optimal reaction conditions the highest conversion of cyclohexene was 52.6% with 73.5% epoxide selectivity. In addition, the catalytic activity was retained after recycling 6 times.