The irreversible conversion of single-site water oxidation catalysts (WOC) into the more rugged catalysts structurally related to [(trpy)(5,5’-X₂-bpy)Ru^IV(μ-O)Ru^IV(trpy)(O)(H₂O)]⁴⁺ (X = H, 1-dn⁴⁺; X = F, 2-dn⁴⁺) represents a critical issue in developing active and durable WOC. In this work, the electrochemical and acid-base properties of 1-dn⁴⁺ and 2-dn⁴⁺ were evaluated. In-situ resonance Raman spectroscopy was employed to characterize species formed upon stoichiometric oxidation of single-site catalysts demonstrating the formation of high oxidation states mononuclear Ru=O and RuO-O complexes. Under turnover conditions, the dinuclear intermediates, 1-dn⁴⁺ and 2-dn⁴⁺, as well as the previously proposed [Ru^VI(trpy)(O)₂(H₂O)]²⁺ complex (3²⁺) are formed. 3²⁺ is a pivotal intermediate that provides access to the formation of dinuclear species. Single crystal X-ray diffraction analysis of the isolated complex [Ru^IV(O)(trpy)(5,5’-F₂-bpy)]²⁺ reveals a clear elongation of the Ru-N bond located in the trans position to the oxo group, documenting the weakness of this bond which promotes the release of the bpy ligand and the subsequent formation of 3²⁺.