Abstract: | A kinetic reinvestigation of the title redox system in aqueous alkaline media at 35°C and an ionic strength of 0.5 mol dm?3 shows that the reaction follows a pseudosecond-order Fe(CN) disappearance. While varying phenol]0 and OH?] exhibit a linear influence on the pseudo-second-order rate constant, varyingFe(CN)]0 and Fe(CN)]0, initially taken, have a complicated inhibitory effect on the same. The major phenoloxidation products isolated under a chosen condition are 2,2′- and 4,4′- dihydroxydiphenyl. Results are interpreted in terms of a probable mechanism which envisages a reversible formation, by the first one-electron transfer, of a reactive phenoxy radical (PhO˙) which on the second one-electron transfer forms a less reactive ion-pair intermediate (stabilized by the Fe(CN) produced) to decompose rate-determiningly to phenoxonium cation (PhO+) and Fe(CN), the product-formation steps being very rapid and kinetically indistinguishable. |