REDUCTION OF THE BIS(PENTANE-2,4-DIONATO)DIAQUO MANGANESE(III) COMPLEX BY HYDROXYLAMINE AND L-ASCORBIC-ACID IN AQUEOUS-SOLUTION

The kinetics and mechanisms of the reduction of bis(pentane-2,4-dionat o)diaquo manganese(III), [Mn(pd)2(H2O)2]+ by hydroxylamine and L-ascor bic acid have been investigated in aqueous solution at 25-degrees-C an d ionic strength 0.5 mol dm-3. Mechanisms are proposed which account s atisfactorily for the kinetic data. Inner-sphere mechanisms appear to be operative for both reductants. In the case of hydroxylamine, the co mplex dependency of k(obs) on the reductant concentration strongly sup ports this view.