Donor-Acceptor Triads Composed of Tetrathiafulvalene and Benzoquinone Fused by Benzene-Spacers: Application to the Positive Electrode Materials for Use in Rechargeable Batteries

Donor-acceptor triads composed of tetrathiafulvalene (TTF) and benzoquinone (BQ) fused by a benzene-spacer (3, 4) were successfully synthesized. In the cyclic voltammetry, the bis[(2-ethyl)hexylthio]-4 (4e) exhibited five-pairs of one-electron transfer waves corresponding to the formation of both reduction and oxidation states from −1 to +4. The 3/Li cell exhibited high discharge energy density exceeding 700 mWh g−1.