Synthesis And Optical Properties Of Metal (Mn And Gd) Porphyrins

Metalloporphyrin is one of the porphyrin derivatives with macromolecular ringstructure. It can be a carrier of energy conversion and material transportation in vivo,and also serve as various functional materials. Recently, metalloporphyrins withparamagnetism are becoming research focus, for these types of metalloporphyrinswill be applied in biomedical field as the magnetic resonance imaging contrastagents. So it is very meaningful to study the new type of metalloporphyrincomplexes with such characteristic. The purpose of this study is the preparation andseparation of two new-type paramagnetic metalloporphyrins, and to explore thesynthesis methods and the nature of metalloporphyrins.The synthesis and photosensitivity of the hematoporphyrin monomethyl ethermanganese was studied. Manganese chloride and hematoporphyrin monomethylether were reacted by DMF methods in140℃cooling water refluxed1hour. TheUV-visible spectrum was tested and found the Q band appeared two characteristicabsorption peaks at462nm and550nm, respectively, which belonged to themetalloporphyrins. Methanol was selected as a suitable mobile phase by thinchromatography, and was applied to separated the product in silica gel columnchromatography. The measurement of the Fourier transform infrared spectrum ofthe separation product by squash method, and the results were found thecharacteristic infrared absorption of N-H bond at970cm^-1was disappeared, but thenitrogen-metal characteristic absorption at1114cm^-1and1093cm^-1respectivelywere observed. The hematoporphyrin monomethyl ether manganese fluorescencequenching was tested by fiber spectrometer which excited by405nm semiconductorlaser. A novel fluorescent probe molecular called MCLA was used to tested thephotosensitivity of hematoporphyrin monomethyl ether manganese and found itsphotosensitivity disappears.The synthesis and characterization of the hematoporphyrin monomethyl ethergadolinium was studied. Gadolinium chloride and hematoporphyrin monomethylether were reacted by imidazole methods in210℃refluxed2hours under argonatmosphere. The UV-visible absorption spectrum was tested and found the Q bandappeared two characteristic absorption peaks at538nm and571nm respectively, while the Soret band absorption at407nm. A sand core filter was applied to purifythe product and imidazole. With m/z=803as the mass peak of the hematoporphyrinmonomethyl ether gadolinium was observed by mass spectrometry analysis. Thefluorescent spectrum of hematoporphyrin monomethyl ether gadolinium showedQ（0,1） transition at the710nm, while Q（0,0） transition is split into two weakfluorescence peaks at582nm and629nm, respectively. A fluorescent probemolecular called MCLA was used to tested the photosensitivity of hematoporphyrinmonomethyl ether gadolinium and shows its photosensitivity.The synthesis reaction of transition metal porphyrins and rare earth metalporphyrins process with spectroscopy were studied by three different mainmethods like DMF method, microwave excitation method and imidazole method.The determination the synthesis reaction process of metalloporphyrins depended onthe real-time monitoring the spectral changes of the reaction solution. The resultsshow as follow, the synthesis reaction is difficult to process by DMF method underlow temperature, the side effects impact the use of microwave method, so DMFmethod under150℃for the synthesis of transition metalloporphyrin andimidazole method under210℃for synthesis of rare earth metalloporphyrin aremore desirable.Based on the above study, hematoporphyrin monomethyl ether manganese andhematoporphyrin monomethyl ether gadolinium were successfully synthesizedproved by infrared spectroscopy and mass spectrometry, respectively, which laid thefoundation for further study in biomedical field.