A number of 3-monosubstituted bis (thienylvinyl) thiophenes, suitable for the preparation of electronically-variable poly (thienylenevinylene) s have been synthesized for the first time. These materials have been characterized by both NMR spectroscopy and mass spectrometry, and a single crystal X-ray structure analysis of (E, E)-3-(5, 5-dimethyl [1, 3] dioxin-2-yl)-2, 5-bis (2-thien-2-ylvinyl) thiophene has shown that the planarity of the ...