The design and synthesis of ruthenium tris-diimine photosensitizers appropriately functionalized to be (i) anchored onto transparent conductive oxides (TCO) and (ii) covalently coupled with a water-splitting catalyst represents an important target for solar fuel production in dye-sensitized photoelectrochemical cells (DS-PECs). In this study, two different synthetic routes to prepare heteroleptic [Ru(4,4 '-(CH2PO3Et2)(2)-bpy)(2)((NN)-N-<^>)](PF6)(2) complexes are evaluated, the scope and limitations of the organometallic pathway involving half-sandwich eta(6)-arene ruthenium complexes as synthetic intermediates being especially studied. The spectroscopic and electrochemical characterization of a series of novel structures varying by the nature of the third diimine (NN)-N-<^> ligand is reported.