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The electrocatalytic ligand substitutions of Cp’Mn(CO)2(NCMe) and Cp’Mn(CO)2(pyr) with phosphines and phosphites have been investigated by derivative cyclic voltammetry (DCV) at sweep rates that are sufficiently fast to preclude high catalytic turnovers on the experimental time scale. Digital simulations have established that a single working curve may be used to analyze the DCV data, provided that the substrate is more readily oxidized than the product by 250 mV or more. Rate constants and activation parameters were obtained for the reactions between Cp’Mn(CO)2(NCMe)+ and PPh3 and P(OMe)3, and between Cp’Mn(CO)2(pyr)+ and PEt3 and PBu3. Excellent agreement is observed between the kinetic data obtained with this technique and previously reported values that were obtained under conditions that allowed for high catalytic turnover numbers.

One of the most direct ways to determine the free energy change of a reaction in solution is to measure the corresponding reversible electrode potential. This places the study of electrode processes at a high level of importance in the search for understanding of the chemistry of reactive intermediates. Combined with gas phase ionization potential and electron affinity data, electrode potential measurements can provide information about fundamental processes such as solvation as well as bonded and non-bonded interactions between solution species. In this discussion we will focus on the formation of positive and negative radical ions as well as the corresponding doubly charged ions. A complete review of this topic is beyond the intended scope and the coverage reflects the research interests of the authors.