Viologen molecular switches incorporating bis(acetylacetonato) cobalt(II) and bis(3- chloroacetylacetonato) cobalt (II) complexes

Cobalt(II) complexes: CoA and CoACl are synthesized. Treatment of CoA with 10 equivalents of 4,4-bipyridine (Bpy) in acetone afforded adduct complex CoA-Bpy. These three cobalt(II) complexes are characterized by FT-IR, mass and UV-Visible absorption spectrometries besides thermal and XRD analysis. The interactions of the complexes CoA and CoACl with Bpy to afford the adduct complexes are studied by UV-Visible absorption spectrometry. The interactions of the complexes CoA and CoACl with propylene linked bis-viologen (V2+A2.2PF6-) yield the adduct complexes coordination of V2+2.2PF6- to cobalt(II) ion within cobalt(II) complexes. Then, switching motion of V2+2.2PF6- coordinated to Co(II) ion was triggered by two electrons reduction.