Two methods are reported for the incorporation of carboxylate substituents on polypyridyl ligands coord- inated to ruthenium(II) centres. In the first, a precursor complex is synthesized with ethoxycarbonyl groups which are subsequently base-hydrolysed to produce the carboxylate in high yield (–CO2Et → –CO2H). In the second method, ruthenyl (RuIV =O) species were used to chemically catalyse the electochemical oxidation of methyl substituents on the ligands of a precursor complex to produce the target carboxylate species (–CH3 → –CO2H).