Isolation and X‐ray Structural Determination of Both Folded and Twisted Conformers of Bis{4H,8H‐4‐(dicyanomethylene)‐benzo[1,2‐c:4,5‐c′]bis[1,2,5]thiadiazol‐8‐ylidene}, an Overcrowded Ethylene with High Electron Affinity

Reversible machano- and thermochromic behavior are-features of the title bis(tricyclic) olefin. These characteristics are a consequence of the different proper ties of the interconvertible folded and twisted confomers. Despite the severe molecular deformation the conductive charge-transfer complexes and stable salts of the radical anion could be isolated due to their strong electron affinity.