ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
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)63- disappearance. While varying [phenol]0 and [OH-] exhibit a linear influence on the pseudo-second-order rate constant, varying[Fe(CN)63-]0 and [Fe(CN)64-]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)64- produced) to decompose rate-determiningly to phenoxonium cation (PhO+) and Fe(CN)64-, the product-formation steps being very rapid and kinetically indistinguishable.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550190207
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