Cyclometalated Ru^II Complexes with Improved Octahedral Geometry: Synthesis and Photophysical Properties

Abstract

Cyclometalated bis-tridentate ruthenium(II) complexes incorporating 2,6-diquinolin-8-ylpyridine ligands and exhibiting broad visible absorptions are described. A [Ru(N(wedge)N(wedge)N)(N(wedge)C(wedge)N)](+) complex based only on ligands with expanded bite angles has a metal-to-ligand charge-transfer excited-state lifetime of 16 ns, which is attributed to a strong ligand field and therefore reduced deactivation via metal-centered states.