title: Kinetics and mechanism of oxidation of promazine and promethazine by ferric perchlorate.
abstract: The equilibrium constants, kinetics, and mechanism of promazine and promethazine oxidation by ferric perchlorate were investigated at different temperatures and acidities using a stopped-flow spectrophotometric technique. The overall reaction can be represented as follows: (formula: see text) where P+ represents the radical cation corresponding to the phenothiazine derivative. The equilibrium quotients were evaluated at 1.00 M HClO4, 25.0 degrees, and ionic strength 1.0 M. The kinetics of reaction follow the equation: -d[P] divided by dt = k1[Fe3+][P]-k-1[Fe2+][P+] The rate constants k1 and k-1 are independent of acidity and are related to the corresponding equilibrium quotients.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D007700:Kinetics; D008027:Light; D010084:Oxidation-Reduction; D010472:Perchlorates; D011395:Promazine; D011398:Promethazine; D013053:Spectrophotometry
chemical_list: D010472:Perchlorates; D011398:Promethazine; D011395:Promazine