Complex formation equilibrium processes of the (N,N) donor containing 2,2'-bipyridine (bpy) and ethylenediamine (en) with (η 5 -pentamethylcyclopentadienyl)rhodium(III) were investigated in aqueous solution via pH-potentiometry, 1 H NMR spectroscopy, and UV-Vis spectrophotometry in the absence and presence of chloride ions. 2+ , and formation of ternary HSA-RhCp*-ligand adducts was proved. In the case of the deferiprone complex, the RhCp* fragment is cleaved off when HSA is loaded with low equivalents of the compound.