Oxidation of benzenediols by the iron(III) tetracyano bipyridyl ion: a high pressure stopped-flow kinetics study
作者:Colin D. Hubbard、Hari C. Bajaj、Rudi van Eldik、John Burgess、Nicholas J. Blundell
DOI:10.1016/s0020-1693(00)82986-2
日期:1991.5
protonated species of the iron(III) complex. Application of pressure, up to 1 kbar, gives rise to more rapid oxidation, and within experimental error, the volume of activation, ΔV* is substrate independent (ΔV* = −18 cm3 mol−1). The values of ΔS* are compatible with this finding. Kinetic and activation parameters are treated within the framework of an outer-sphere electron transfer mechanism.
摘要铁(III)四氰基2,2-联吡啶离子[Fe(CN)4(bpy)]-易氧化苯二醇,邻苯二酚(1,2-二羟基苯),4-叔丁基邻苯二酚(1,2- (2-羟基-1,4-二羟基苯)和(2-甲基-1,4-二羟基苯)水溶液中的甲基对苯二酚。通过在2.5-6的pH范围内的停流分光光度法研究了动力学。在该区域的下端,反应与pH无关,并且对于三种二醇,在298.2 K处的二阶速率常数分别为50、68和477 mol-1 dm3 s-1。在pH依赖区(3–6)中,缓冲溶液中的速率因铁(III)络合物质子化程度不同而变化。施加高达1 kbar的压力会导致更快速的氧化,并且在实验误差范围内,活化量,ΔV*是与底物无关的(ΔV* = -18 cm3 mol-1)。ΔS*的值与此结果兼容。在外层电子转移机制的框架内处理动力学和活化参数。