A Synergetic Experimental and Computational Approach Towards a Better Comprehension of Redox Reactions of N3 Dye [cis‐bis(Isothiocyanato)‐Ruthenium(II)‐bis(2, 2’‐Bipyridine‐4,4’‐Dicarboxylic Acid] in Solution

Abstract

Charge transfer processes in coordination compounds with labile ligands are strongly dependent on the coordination sphere. Various intermediate steps involve creation of new species during the redox reactions in solution. For the prototypical N3 dye [cis–bis(isothiocyanato)‐ruthenium(II)‐bis(2, 2’‐bipyridine‐4,4’‐dicarboxylic acid], its electro‐oxidation transformation involves a knotty mechanism in which the coordination of the Ru(II) with SCN‐ ligands is modified. This process produces reactive chemical species that are not easily identified during the spectroelectrochemical characterization. TDDFT calculated absorption spectra were used as an easy and trustworthy tool to identify actual intermediates amongst different possible products in coordination compound transformation. The evolution of the spectra demonstrates, by an experimental and theoretical synergetic approach, the complicated reaction processes, and allows the identification of intermediate and final species both in DMSO and THF solvents. By combining EPR/UV‐Vis spectroscopies and TDDFT calculations we show previously undetected Ru(III) species in the N3 dye at higher potentials in both solvents.

Casiopeinas® third generation, with indomethacin: synthesis, characterization, DFT studies, antiproliferative activity, and nanoencapsulation

“…To calculate redox potentials, we followed previous reports that have proven to be useful for transition metal complexes, [77][78][79] and in which geometries of ferrocene (Cp 2 Fe) and ferrocenium ([Cp 2 Fe] + ) in the eclipsed conformation (D 5h ) were taken into account and optimized in the gas phase. Gas phase and solvation DG energies were calculated by the same level of theory and using SMD continuum solvation model 80 and DMSO to simulate the same environment of the electrochemical experiments.…”