AbstractPolyesterification products with tetrathiafulvalene units3a–ewere prepared from tetrathiafulvalenedicarbonyl dichloride (1) and various α,ω‐diols (2a–e) containing 2 to 16 methylene groups. The red to brown products3a–ewith melting points between 235°C and 128°C are insoluble in all common organic solvents, except for3ewhich is soluble in hot DMF. Molecular weights determined by vapor pressure osmometry as well as from elemental analysis data have been found to be ≥2000. The structures were proved by IR, MS, and electronic spectra. The electrical conductivities of3a–eare between 4 . 10‐8and 4 · 10‐13Ω‐1· cm‐1. In TCNQ complexes the electrical conductivities are enhanced by one t