title: Phenylcyanamide ligand control of photo-induced linkage isomerism.
abstract: The photo- and electrochemically induced linkage isomerism of six new complexes [Ru(bpy)2(L)(dmso-S)](+), where dmso is dimethylsulfoxide, bpy is 2,2'-bipyridine, and L(-) is pentachloro-, 2,3,5,6-tetrachloro-, 2,4,5-trichloro-, 2,4-dichloro-, 4-chloro-, and unsubstituted phenylcyanamide anion, were investigated. The quantum yields of linkage isomerism forming the metastable [Ru(bpy)2(L)(dmso-O)](+) complexes are shown to decrease with increasing donor properties of the phenylcyanamide ligand, and it is suggested that the donor properties of the cyanamide ligand stabilize the [Ru(bpy)2(L)(dmso-S)](+) complexes in the (3)MLCT excited state. The cyclic voltammetry of these complexes showed two oxidation processes: a phenylcyanamide L(0/-) couple (an assignment supported by density functional theory (DFT) calculations) and a Ru(III/II) couple at more positive potential. Upon oxidation to Ru(III), the complexes rearranged to form Ru-O linkage isomers, and the scan rate dependent voltammograms permitted estimates of the rates of linkage isomerism.
authors.affiliation: Chemistry Department, Carleton University , Ottawa, Ontario K1S 5B6, Canada.
authors.forename: Mohommad M R
authors.initials: MM
authors.lastname: Choudhuri
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Crutchley