Synthesis, Crystal Structure, and Redox and Photophysical Properties of Novel Bisphosphinoaryl RuII-Terpyridine Complexes

Novel organometallic [Ru(PCP)(tpy)]Cl complexes, containing the terdentate coordinating monoanionic bisphosphinoaryl ligands [C 6 H 3 (CH 2 PR 2 ) 2 -2,6] - (PCP) (R = Ph ( 11 ); i Pr ( 12 )) and 2,2‘:6‘,2‘ ‘-terpyridine, have been synthesized by two different synthetic pathways in good yields. The molecular structure in the solid state of [Ru{C 6 H 2 (CH 2 PPh 2 ) 2 -2,6}(tpy)](OTf) ( 14 ) has been determined by X-ray crystallography. The spectroscopic and electrochemical properties of the [Ru(PCP)(tpy)]Cl complexes were compared with those obtained for [Ru{C 6 H 3 (CH 2 NMe 2 ) 2 -2,6}(tpy)](Cl) ( 3 ) containing the monoanionic bisaminoaryl ligand [C 6 H 3 (CH 2 NMe 2 ) 2 -2,6] - (NCN). The obtained results revealed that substitution of the NCN-pincer ligand by PCP-pincer ligands offers a powerful tool to tune the redox and photophysical properties as well as the reactivity of the ruthenium(II) metal centers in the resulting photoactive monomeric species.