Reprint of: Structural, electronic and acid/base properties of [Ru(bpy)(bpy(OH)2)2]2+ (bpy = 2,2′-bipyridine, bpy(OH)2 = 4,4′-dihydroxy-2,2′-bipyridine)

We have synthesized the complex [Ru(bpy)2(bpy(OH)2)]2+ (bpy =2,2′-bipyridine, bpy(OH)2 = 4,4′-dihydroxy-2,2′-bipyridine). Experimental results coupled with computational studies were utilized to investigate the structural and electronic properties of the complex, with particular attention paid toward the effects of deprotonation on these properties. The most distinguishing feature observed in the X-ray structural data is a shortening of the CO bond lengths in the modified ligand upon deprotonation. Similar results are also observed in the computational studies as the CO bond becomes double bond in character after deprotonating the complex. Electrochemically, the hydroxy-modified bipyridyl ligand plays a significant role in the redox properties of the complex. When protonated, the bpy(OH)2 ligand undergoes irreversible reduction processes; however, when deprotonated, reduction of the substituted ligand is no longer observed, and several new irreversible oxidation processes associated with the modified liga...