Ethylenedioxy-Containing Tetrathiapentalene Derivative with Ethylthio Chains, C2TEO-TTP

A new oxygen-containing (pi)-electron donor having ethylthio chains, C2TEO-TTP (2-[4,5-bis(ethylthio)-1,3-dithiol-2-ylidene]-5-(4,5-ethylenedithio-1,3-dithiol-2ylidene)-1,3,4,6-tetrathiapentalene), has been synthesized. Single-component C2TEO-TTP forms a (beta)ʹ-like dimerized structure. The 2 : 1 salts with PF6-, ClO4-, and AsF6- have a uniform (beta)-type structure isostructual to the ethylenedithio analog, (C2TET-TTP)2ClO4, and are metallic down to liquid helium temperatures. On the other hand, (C2TEO-TTP)2Au(CN)2 has dimeric donor arrangement, and shows hysteretic temperature dependence of the conductivity.