ELECTRON-TRANSFER REACTIONS OF IRON(III)-POLYPYRIDYL COMPLEXES WITH ORGANIC SULFIDES

The redox reactions of FeL(3)(3+) (where L = 2,2'-bipyridine, 4,4'-dim ethyl-2,2'-bipyridine and 1,10-phenanthroline) with alkyl aryl sulphid es in aqueous methanol have been studied by the spectrophotometric tec hnique. The comparison of the experimental rate constant data with the values estimated from Marcus cross-reaction relationship led to the c onclusion that the single electron transfer from sulphide to FeL(3)(3) is the rate controlling step. The kinetic data yield 1.0 x 10(7) M(- 1)s(-1) for the ArSR/Ars(+.) R self-exchange rate constant at 25 degre es C.