Three series of novel push–pull 5‐arylthieno[3,2‐b]thiophene derivatives functionalized with potent electron‐withdrawing terminal moieties have been synthesized in moderate to excellent yields by Suzuki coupling followed by Knoevenagel condensation. These novel chromophores show intense absorption in the near‐UV region through to the orange visible region, related to a strong intramolecular charge‐transfer transition. By combining a strong donor and acceptor, large fluorescence quantum yields were achieved as well as large two‐photon absorption responses. Interestingly, due to the improved rigidity and electronic delocalization provided by the thienothiophene moiety (as compared with the bithiophene unit), higher one‐ and two‐photon brightness values have been achieved. As a result, several new fluorescent dyes showing enhanced brightness and tunable fluorescence (ranging from the blue to the NIR region) have been obtained that have potential for bioimaging applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.