Thermal studies of cobalt, iron and tin metalloporphyrins

A free-base tetraphenyl porphyrin (TPP) and its corresponding metalloporphyrins (MTPP) where M = Co, Fe and Sn were synthesized and characterized by UV-visible spectroscopy, FTIR and (1)Hnmr spectroscopy. Thermal studies of these porphyrins were carried out in synthetic air from room temperature to 800 A degrees C using thermal analyser. The residues of MTPP after thermal treatment were qualitatively analysed, which showed the presence of corresponding metal oxides. Further, the above MTPP were subjected to thermogravimetry-evolved gas and mass spectrometry (TG-EGA-MS) analysis for the detailed information about evolved gases at their corresponding decomposition temperatures. This information may be used to predict the probable mechanism for ring opening of the macromolecular porphyrins.