Acentric Polymeric Chains in Radical Cation Salts of Tetrathiafulvalene Derivatives with the p‐Carboxybenzenesulfonate Anion

The noncentrosymmetric p‐carboxybenzenesulfonate anion afforded, in electro‐oxidation experiments with bis(ethylenedithio)tetrathiafulvalene (BEDT‐TTF), the low‐gap semiconductor (room‐temperature conductivity: 18 S cm–1) mixed‐valency salt BEDT‐TTF2[O3S‐C6H4‐CO2H], which is noncentrosymmetric due to head‐to‐tail arrangement of the anions, whereas EDT‐TTF‐CONHMe (EDT‐TTF = ethylenedithiotetrathiafulvalene) afforded the fully oxidized centrosymmetric salt [EDT‐TTF‐CONHMe+][HO2C‐C6H4‐SO3–] in which the driving force for the crystal packing is the existence of strong hydrogen‐bonding interactions between the anions and the amido groups of the cations.