Kinetics of the oxidation of ascorbic acid and substituted 1,2- and 1,4-dihydroxybenzenes by the hexacyanoruthenate(III) ion in acidic perchlorate media
作者:J. Mark A. Hoddenbagh、Donal H. Macartney
DOI:10.1039/dt9900000615
日期:——
The kinetics of oxidation of ascorbic acid and a series of substituted 1,2- and 1,4-dihydroxybenzene compounds (H2Q) by [Ru(CN)6]3– have been investigated in acidic perchlorate media. The inverse dependences of the rate constants on acid concentrations for 2,3-dicyano-1,4-dihydroxybenzene, 4,5-dihydroxybenzene-1,3-disulphonate, and ascorbic acid have been attributed to concurrent rate-determining pathways
在酸性高氯酸盐介质中,已研究了[Ru(CN)6 ] 3–对抗坏血酸和一系列取代的1,2-和1,4-二羟基苯化合物(H 2 Q)的氧化动力学。速率常数与2,3-二氰基-1,4-二羟基苯,4,5-二羟基苯-1,3-二磺酸盐和抗坏血酸的酸浓度成反比,这归因于涉及该过程的同时的速率决定途径。- [Ru(CN)6 ] 3-氧化H 2 Q或HQ的电子为相应的半醌或抗坏血酸自由基中间体。根据马库斯关系,交叉反应速率常数已与半醌或抗坏血酸还原电位相关,以产生[Ru(CN)6 ] 3- [Ru(CN)6 ] 4–电子自交换速率常数(1.0±0.8)×10 5 dm 3 mol –1 s –1。将其与其他低自旋d 5 - d 6过渡金属配合物对进行了比较,并就内球和溶剂重组能进行了讨论。