Summary
Kinetic results for reaction of the title complex with oxalate ion have been reinterpreted in terms of a simple dissociative mechanism in which loss of ligand is rate determining. Competition between the ligand and oxalate ion for the dissociated reactive intermediate causes the observed rate constant to rise to a limiting value with increasing oxalate ion concentration. This rate limit is equal to the rate of dissociation. In agreement with this mechanism, rate constants for reaction of four other related iron(II) complexes with an excess of a range of poly carboxylates were found to be similar to their respective rates of aquation, so demonstrating that polycarboxylares act as scavengers rather than nucleophiles in these reactions.
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References
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Burgess, J., Twigg, M.V. On the reaction of oxalate ion withtris-3-(2-Pyridyl)-5, 6-bis-(4-sulphophenyl)-1,2,4-triazine iron (11) in aqueous solution: Kinetics of dissociation of low-spin iron(II) complexes in the presence of polycarboxylate ions. Transition Met Chem 3, 88–90 (1978). https://doi.org/10.1007/BF01393516
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DOI: https://doi.org/10.1007/BF01393516