摘要
The kinetics of the reduction and demetalization of hydroxooxo [ 5, 10, 15, 20-tetrakis ( p-sulfonatophenyl ) porphyrinato] molybdenum (V) ,OMo(V) (OH)TPPS ,by ascorbic acid(i. e. Vitamine C,abbr. H2Asc) ,have been studied in aqueous so-lutions,I=0. 10(KC1) at 30 or 35℃. The reactions ivere run under pseudo-first-order conditions with ascorbic acid in at least 30 fold excess over Mo-porpkyrin. Pseudo-first-order rate constants, kabsd, obtained by monitoring the appearance of TPPS peak at 413. 3mm. The experimental data give a good fit to d[TPPS]/dt= (kl-+k2 [OH-]K3Ka2,[H2Asc]/(Ka2 + [H+]))[Mo(V)P](l)where P rep-resents the porphyrin,the rate constants K1,K2,K3 and Ka2 are KI = 2.185XI0-3,K2 =3. 624X10-2,K3 = 3. 210,Ka2 = 1. 29X10-12 at 35℃
The kinetics of the reduction and demetalization of hydroxooxo [ 5, 10, 15, 20-tetrakis ( p-sulfonatophenyl ) porphyrinato] molybdenum (V) ,OMo(V) (OH)TPPS ,by ascorbic acid(i. e. Vitamine C,abbr. H2Asc) ,have been studied in aqueous so-lutions,I=0. 10(KC1) at 30 or 35℃. The reactions ivere run under pseudo-first-order conditions with ascorbic acid in at least 30 fold excess over Mo-porpkyrin. Pseudo-first-order rate constants, kabsd, obtained by monitoring the appearance of TPPS peak at 413. 3mm. The experimental data give a good fit to d[TPPS]/dt= (kl-+k2 [OH-]K3Ka2,[H2Asc]/(Ka2 + [H+]))[Mo(V)P](l)where P rep-resents the porphyrin,the rate constants K1,K2,K3 and Ka2 are KI = 2.185XI0-3,K2 =3. 624X10-2,K3 = 3. 210,Ka2 = 1. 29X10-12 at 35℃
