Study On Synthesis Of Chlorophyll Metalloporphyrins And Aerobic Oxidation Of Cyclohexene

Metalloporphyrins complex have a good ability to transfer electrons. AsCytochromeP-450, metalloporphyrins can improve the activity of oxygen and exhibit highercatalytic ability and selectivity under mild conditions. The development of efficient,inexpensive metal porphyrin biomimetic catalysts and the research of the relationship betweenmetalloporphyrins structural factors and its catalytic oxidation activity is an important subjectin the field of metal porphyrin biomimetic catalysis.According to the relationship between the biomimetic catalysts structure and theircatalytic activity, as well as the structure features of chlorophyll molecules and their chemicalproperties, six kinds of chlorophyll derivatives such as pheophorbide a、methyl pheophorbidea、pyropheophorbide a、methyl pyropheophorbide a、chlorine e6dimethyl ester and methylprotopyropheophorbide a were synthesized by modifying of the chemical structure ofchlorophyll a which was a widespread natural porphyrins. After confirming these compoundsstructures, the change characteristics of UV-Vis and Infrared spectra between them wereanalyzed profoundly. Six kinds of iron (manganese) porphyrin complex were synthesized andwere used to catalyze the oxidation of cyclohexene under the conditions of atmosphericatmosphere, when molecular oxygen was used as the source of oxygen. The influence of theoutside substituents on the chlorophyll porphyrin ring and their polarity on the substratecyclohexene oxidation performance were analysed by comparing of the experimental data. Theresults indicated that esterification products of chlorophyll iron (manganese) porphyrins haveexcellent catalytic properties on the substrate cyclohexene oxidation, the conversion andselectivity of cyclohexene oxidation products were higher than non-esterified chlorophyllporphyrins products. To the same chlorophyll porphyrin ring, manganese complex performedhigher catalytic activiIy and a higher cyclohexene conversion than iron complex. Iron(manganese) complex performed a higher selectivity for cyclohexanone. Among12types ofsynthesized chlorophyll iron (manganese) complexes, manganese methyl pyropheophorbide awas the best biomimetic catalyst for i’t highest cyclohexene conversion.