Hexachloroiridate(IV) oxidation of benzenediols in binary aqueous solvent mixtures: Solvation and reactivity

Kinetic parameters are reported for hexachloroiridate (IV) oxidation of t-butyl-catechol (4-t-butyl-benzene-1,2-diol), hydroquinone (benzene-1,4-diol) and its 2-t-butyl derivative in binary aqueous mixtures containing methanol, ethanol, t-butyl alcohol, acetone, dimethyl sulfoxide, or dimethylformamide. Solubilities are reported, and transfer chemical potentials thence derived, for hydroquinone in a range of such media and for catechol, 2,4-bis-(t-butyl)catechol, methylhydroquinone and t-butyl- hydroquinone in methanol-water mixtures. On the basis of a selection of these kinetic and thermodynamic rnyesults we have analysed reactivity trends for several of these hexachloroiridate(IV) oxidations into initial state and transition state contributions