Title: Linkage isomerization and electrochemical behavior of two geometrical isomers of dichlorobis(dimethylsulfoxide)bis(<i>t</i>-butylpyridine)ruthenium(II)
Abstract:The reaction of cis-[RuCl 2 (dmso) 4 ] (dmso = dimethylsulfoxide) with 4-tert-butylpyridine (tbpy) in chloroform leads to the all cis (ccc) and the cis,cis,trans (cct) geometrical isomers of [RuCl 2 (...The reaction of cis-[RuCl 2 (dmso) 4 ] (dmso = dimethylsulfoxide) with 4-tert-butylpyridine (tbpy) in chloroform leads to the all cis (ccc) and the cis,cis,trans (cct) geometrical isomers of [RuCl 2 (S-dmso) 2 (tbpy) 2 ]. The cct isomer exhibits a reversible cyclic voltammogram, ascribed to the Ru III/II redox couple with E 1/2 = 1.12 V versus SHE. The ccc isomer can be oxidized at E 1/2 = 1.27 V; however, the oxidized species undergoes a relaxation equilibrium, (K s→o = 1.59), involving the S-to-O linkage isomerization of a coordinated dmso ligand (k s→o = 1.9 s −1 and k O→S = 1.2 s −1 ). The isomerization reaction in the Ru III ccc isomer is discussed in terms of the competitive effects between the S-bound dmso and the tbpy ligands.Read More