Photochemical reaction of magnesium tetraphenyl porphyrin with sulfur dioxide

The photochemical reaction of magnesium tetraphenyl porphyrin（MgTPP） with sulfur dioxide（SO;） was investigated in dichloromethane（CH;Cl;） by steady-state fluorescence,UV-vis absorption,MS,and XRD spectroscopic techniques.These spectra showed that under irradiation MgTPP reacted with SO;to form 1:1 molecular adduct at first step.During the process of keeping irradiation and maintaining the flow of SO;,SO;was reduced into S;by MgTPP and the results were detected using MS and XRD techniques.Understanding the photochemical reaction of MgTPP with SO;is of key interest in elucidating fundamental photochemical reaction mechanisms associated with this class of chlorophyll in the presence of SO;.