Photochromic sexithiophenes were prepared by oxidative electrochemical coupling of terthiophenes. The redox properties in the open state are typical of sexithiophenes. Ring closure of both photochromic units leads to a decrease in the energy of the LUMO orbitals with little affect on the energy of the HOMO orbitals. The photochemical tuning of the conjugation of a molecular wire is achieved by combining dithienylethene units with a sexithiophene.
Org. Lett.

Areephong, J., Hurenkamp, J. H., Milder, M. T. W., Meetsma, A., Herek, J., Browne, W. R., & Feringa, B. L. (2009). Photoswitchable sexithiophene-based molecular wires. Org. Lett., 11, 721–724. doi:10.1021/ol8028059