Synthesis of meso-tetra(4-n-ethylpyridyl)metalloporphyrin catalysts and characterization of catalytical performance

Quaternary ammonium cationic meso-tetra(4-N-ethylpyridyl)porphyrin and metalized compounds thereof,including iron,cobalt,copper,zinc,manganese complexes,Br-as the counter ion,were designed and synthesized according to two pathways,and characterized with UV-Vis,IR,MS,EA and the like to confirm their desirable structures.Furthermore,the characterization of catalytical performances concerning these catalysts,were carried out with the preparation of p-nitrobenzoic acid from p-nitrotoluene by the catalytical oxidation of dioxygen in basic methanol solutions as the model reaction.It was found that these catalysts,including the ligand free of metal,were remarkably active to catalyze such reactions,wherein meso-tetra(4-N-ethylpyridyl)porphyrin zinc bromide showed the catalytically outstanding performance,the conversion for the raw material and the selectivity and yield for p-nitrobenzoic acid reached 90.6%,94.0% and 85.2%,respectively.