Photochemically-induced ligand exchange reactions of ethoxy-oxo-molybdenum (V) 5,10,15,20-tetraphenylporphyrin, Mo(V)O(TPP)-OEt, under irradiation at the Soret band region, were investigated. The reactions were performed in chlorinated solvents and followed with ultraviolet-visible spectroscopy, whereas the products were analyzed with FTIR spectroscopy, ESR spectroscopy and gas chromatography. The chloro-oxo(TPP)Mo(V) complex was obtained as the final product, where the chlorine came from the solvent. Nevertheless, these reactions were not photocatalytic, due to the photochemical inertness of the formed chloro-oxo complex, and an excess of ethanol could not initiate a new photocatalytic cycle unless water was added as well, resulting in the formation of the correspondign oxo-Mo(IV) complex. The studied photoassisted reactions of oxoMo(V) porphyrins appear attractive for possible applications in the detection of chlorinated pollutants in sensing devices, but also for the dechlorination of pollutants upon suitable optimization of processing conditions.
Photochemically-induced ligand exchange reactions of ethoxy-oxo-molybdenum(V) tetraphenylporphyrin in chlorinated solvents
MALDOTTI, Andrea;
2006
Abstract
Photochemically-induced ligand exchange reactions of ethoxy-oxo-molybdenum (V) 5,10,15,20-tetraphenylporphyrin, Mo(V)O(TPP)-OEt, under irradiation at the Soret band region, were investigated. The reactions were performed in chlorinated solvents and followed with ultraviolet-visible spectroscopy, whereas the products were analyzed with FTIR spectroscopy, ESR spectroscopy and gas chromatography. The chloro-oxo(TPP)Mo(V) complex was obtained as the final product, where the chlorine came from the solvent. Nevertheless, these reactions were not photocatalytic, due to the photochemical inertness of the formed chloro-oxo complex, and an excess of ethanol could not initiate a new photocatalytic cycle unless water was added as well, resulting in the formation of the correspondign oxo-Mo(IV) complex. The studied photoassisted reactions of oxoMo(V) porphyrins appear attractive for possible applications in the detection of chlorinated pollutants in sensing devices, but also for the dechlorination of pollutants upon suitable optimization of processing conditions.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
