Synthesis and Electronic Properties of D–A–D Triads Based on 3-Alkoxy-4-cyanothiophene and Benzothienothiophene Blocks

3-Alkoxy-4-cyanothiophene units are used as building
block for the synthesis of conjugated donor–acceptor–donor
(D–A–D) triads. The donor part consists of benzothienothiophene
end groups associated with the alkoxy groups of the 3-alkoxy-4-cyanothiophene,
while the central acceptor part is formed by combining the electron-withdrawing
cyano group with thiophene or benzothiadiazole units.