系列水溶性磺酸卟啉的制备、表征及催化性能

摘要

改进磺化路线制备了5种取代基及取代位置不同的水溶性磺酸卟啉,利用氢核磁共振波谱(1H NMR)、傅里叶变换红外光谱(FTIR)、紫外-可见吸收光谱(UV-Vis)及质谱(MS)等手段对产物进行表征及性质研究.将该系列卟啉作为光催化剂,用于催化氧化1,5-萘二酚的反应,主催化产物为5-羟基-1,4-萘二醌,转化率为78%～95%.实验发现,磺酸基团在苯环上的位置以及取代基的数目、电子效应及立体位阻效应均会对催化结果产生影响,其中磺酸根的位置至关重要.动力学研究结果表明该催化氧化过程为一级反应.探讨了该反应的反应机理.%A series of water-soluble sulfonated porphyrins with different substituents and substituted positions has been efficiently synthesized by modifying the traditional sulfonation route,and has been characterized by 1H NMR,Fourier transform infrared spectroscopy(FTIR),ultraviolet-visible spectroscopy(UV-Vis) and mass spectrscopy(MS).These porphyrins were used as photocatalysts for the oxidation of 1,5-dihydroxynaphthalene using H2O2 as oxidant.The product was 5-hydroxy-1,4-naphthoquinone with conversion rates ranging from 78% to 95%.The effects of the position of the sulfonic group on the phenyl ring,the number of substituents,the electron and steric hindrance of the substituent groups on the catalytic activities of the porphyrins have been investigated and the results indicate that all these factors can affect the catalytic activities.The catalytic mechanism has been discussed and the kinetic data show that the catalytic process is a first-order reaction.