Isomerically pure syn-/anti-anthradithiophene derivatives have been developed in the past few years. Although anti-isomers showed higher field-effect mobilities than mixture of isomers have been reported, a detailed comparison of syn-isomer and anti-isomer molecules has not been carried out. In this study, we took newly synthesized pure unsubstituted syn-/anti-anthradithiophenes (ADTs) and compared their single crystal structures, physical properties and semiconducting behavior with a previously studied syn-/anti-dimethylanthradithiophenes (DMADTs). Although the both isomers were typical herringbone packing structures with similar parameters, anti-isomers involved less disordered atoms in the crystal packing. The results from thermal analysis, UV-vis spectra, photo luminescence spectra and cyclic voltammograms of syn-/anti-anthradithiophenes were nearly the in the solid state as well as in solution. However, field-effect transistors showed obvious differences with mobilities of 0.12 cm(2) V(-1) s(-1) for anti-anthradithiophene and 0.02 cm(2) V(-1) s(-1) for syn-anthradithiophene. Because the crystallinity of thin-films measured by X-ray diffraction (XRD) and atomic force microscopy (AFM) seems to be better in syn-isomers, the differences in transistor performance are likely attributed to local defects affecting intermolecular interactions, such as disorder in the crystal packing and charge-dipole interactions.

Poly(silylene-p-phenylene)s bearing an anthrylethynyl, pyrenylethynyl, or terthienyl group as the pendant were obtained in moderate yield, by substitution reactions of poly[ethoxy(methyl)silylenep-phenylene] with the corresponding organolithium reagents in THF. The polymers exhibited photoluminescent (PL) properties in solutions as well as in the films. They were photoactive and irradiation of the films in air with a low-pressure mercury lamp led to a decrease of PL efficiencies, being applicable to PL imaging of the films. The present polymers can be used also as hole-transporting materials in double-layer electroluminescent (EL) devices and the devices with the structure of ITO/polymer film/ Alq3/Mg-Ag emitted a green EL arising from Alq3 emission.

Novel semiconducting polymers consisting of thiophene and anthracene units without alkyl groups were successfully synthesized through soluble precursor polymers and applied to the organic thin-film transistors (OTFTs). Thermal elimination of leaving groups from the precursor polymers by retro Diels−Alder reaction was proved by thermogravimetric analysis (TGA), FT-IR, and UV−vis spectroscopy. The resulting films of the semiconducting polymers showed good surface morphologies even after thermal elimination, resulting in good semiconducting behavior with mobility of 0.015 cm 2 V −1 s −1 in the typical topcontact OTFT. In addition, the devices based on these polymers are stable under ambient conditions and maintained good transistor performance even after being stored in air for 2 months.

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Solution-processable polymers based on strong acceptor benzobis(thiadiazole) (BBT) units were synthesized to form unipolar n-type organic thin-film transistors (OTFTs) that were electronically characterized. These polymers exhibited a narrow band-gap and low LUMO level, resulting in distinct n-type semiconducting properties within the OTFT devices. The BBT–thiazole polymer material showed better electron transport than BBT–thiophene polymers. The use of electron-deficient units was found to be suitable for the realization of the unipolar n-type semiconducting polymers.