Synthesis, Structure, And Electrochemical Properties Of Extended Tetrathiafulvalene Dimers Linked By Flexible Butylene Chain

Tetrathiafulvalene derivatives bridged by butylene units were successfully synthesized. X-ray structure analysis of the dimeric EBDT 1 revealed that C-C bonds have staggered arrangement and all substituents are arranged anti to each other in the butylene bridge. Cyclic voltammograms of the molecules 1 and the fused TTF analog 2 consisted of two-pairs of two-electron and four pairs of two-electron redox waves, respectively. X-ray structure analysis and calculation of overlap integrals of a dicationic salt of unsubstituted-1 (1Aa) indicated that the EBDT units are stacked with strong dimerization. Coin-type cells using the molecule 2 (2Ce) as a positive electrode material showed initial discharge capacity of 179mAhg(-1), initial energy density of 600mWhg(-1), and an average voltage of 3.35V.