The second redox process commences with formation of outer-sphere complex 24 formed by dissociation of the triflate ligand from 23_OTf. Due to the weakly coordinating nature of the triflate anion, the outer-sphere complex 24 is only 9.1 kcal/mol higher in energy than the innersphere complex 23_OTf. The triflate anion within 24 is then predicted to act as a base and through a deprotonation reaction via TS24-25 produces Zwitterion-type complex 25 with an overall activation barrier of 16.2 kcal/mol. The delivery of the resultant triflic acid to the anionic oxygen of the catecholate ligand within 25 gives 26 (a tautomer of 24) from which the second redox process proceeds via transition structure TS26-27. The deprotonation of the hydroxy group in 26 by the triflate anion increases the electron density on the catecholate ligand, resulting in two electrons from it being transferred to I(III) center via the curly arrow mechanism (Figure ). Notably, due to the weakly coordinating nature of the triflate anion, inner-sphere complex 28 is only 4.0 kcal/mol lower in energy than the outer-sphere complex 26. As such, according to our calculations, the overall activation barrier for the second redox step (via TS26-27) is only 12.3 kcal/mol. The triflic acid generated in the last step then reacts with 9 and, consistent with the experimental observations, gives diammonium salt 14 in an exergonic fashion. From the foregoing computational data, we conclude that the ratedetermining step of this transformation is the first redox step via sequence 21_OTf  22_OTf