| Popis: |
Kinetics of the acid-catalyzed disproportionation, followed by demetallation of [tetrakis( p -(trimethylammonio) phenyl)porphinato]silver(II) was studied at 25 °C and μ=0.1 mol dm −3 [NaNO 3 ]. Under the conditions of study, the silver porphyrin exists as dimers in solution. The reaction was found to be first order in dimer and second order in [H 3 O + ], with k , the third-order rate constant=1.28±0.02 mol −2 dm 6 s −1 . Kinetics of aquasilver(I) oxidation of the silver(I) and silver(II) porphyrins are also reported. Oxidation of silver(I) porphyrin by aquasilver(I) is found to be first order each in aquasilver(I) and porphyrin with the overall second-order rate constant=(10.7±0.3)×10 −2 mol −1 dm 3 . Plausible mechanisms for all these reactions are presented. |
