Synthesis and some properties of binuclear ruthenocene derivatives bridged by both ethene and thiophene derivatives

Binuclear ruthenocenes bridged by ethenes and thiophene derivatives, Rc–CHCH–Z–Rc and Rc∗–CHCH–Z–CHCH–Rc∗ (Z = thiophene, thieno[3,2-b]thiophene, and 2,2′-bithiophene; Rc = ruthenocenyl, R∗ = 1′,2′,3′,4′,5′-pentamethylruthenocenyl) were prepared. These complexes showed a one-step two-electron redox wave in the cyclic voltammograms, in contrast to the benzenoid-bridged dinuclear ruthenocenes. The chemical oxidation of the Rc–CHCH–Z–Rc complexes gave no stable oxidized species. The two-electron oxidized species of the Rc∗–CHCH–Z–CHCH–Rc∗ complexes were comparably stable and contained a fulvene-complex type structure.

Graphical abstractBinuclear ruthenocenes bridged by ethenes and thiophene derivatives, Rc–CHCH–Z–Rc and Rc∗–CHCH–Z–CHCH–Rc∗ (Z = thiophene, thieno[3,2-b]thiophene, and 2,2′-bithiophene; Rc = ruthenocenyl, R∗ = 1′,2′,3′,4′,5′-pentamethylruthenocenyl) showed a one-step two-electron redox wave in the cyclic voltammograms. The two-electron oxidized species of the Rc∗–CHCH–Z–CHCH–Rc∗ complexes contained a fulvene-complex type structure.Figure optionsDownload full-size imageDownload as PowerPoint slide