The standard reduction potentials of substituted catechols have previously been determined through kinetic studies of their one-and two-electron oxidation by tris(1,10-phenanthroline) iron (III). From our screening library of 63 compounds, nine compounds overlapped with a library of 15 analytes for which standard reduction potentials were experimentally determined by Pelizzetti et al. For these nine ligands, our analysis unveiled a robust correlation between reduction potentials of the substituted catechols and their corresponding optical responses (Fig. ). Specifically, compounds that underwent facile oxidation elicited more pronounced optical responses than compounds that were more difficult to oxidize (Fig. ). This finding suggested electrochemical properties are significant correlates of optical response, although this observation was based on a relatively small subset of our library. To validate and extend these findings, we aimed to explore whether this observation holds true across the broader range of molecules in our screening library.