A novel highly π-extended heteroarene with eight fused aromatic rings, dianthra[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DATT), was selectively synthesized via a newly developed synthetic strategy, fully characterized by means of single crystal X-ray structural analysis, and examined as an organic semiconductor in thin film transistors. Even with its highly extended acene-like π-system, DATT is a fairly air-stable compound with IP of 5.1 eV. Single crystal X-ray structural analysis revealed its planar molecular structure and the lamella-like layered structure with typical herringbone packing. Theoretical calculations of the solid state electronic structure based on the bulk single crystal structure suggest that DATT affords almost comparable intermolecular orbital couplings between HOMOs (t(HOMO)) with those of dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT), implying its good potential as an organic semiconductor for organic field-effect transistors. In fact, field-effect mobilities as high as 3.0 cm(2) V(-1) s(-1) were achieved with vapor-processed DATT-based devices, which is comparable with that of DNTT-based devices. The molecular ordering of DATT in the thin film state, however, turned out to be not completely uniform; as elucidated by in-plane and out-of-plane XRD measurements, the face-on molecular orientation was contaminated in the edge-on orientation, the former of which is not optimal for efficient carrier transport and thus could limit the mobility.

A new straightforward synthesis of dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT) derivatives from readily available 2-methoxynaphthalenes is described. Thus, newly developed derivatives of DNTT showed very high field effect mobility in the vapor-processed field-effect transistors up to 8 cm(2) V(-1) s(-1).

A new straightforward synthesis of isomerically pure anthra[2,3-b:6,7-b'] -difuran (anti-ADF), -dithiophene (anti-ADT), and -diselenophene (anti-ADS) from readily available 2,6-dimethoxyanthracene is described. The present successful synthesis makes it possible to overview the linear-shaped anti-acenedichalcogenophene compounds, that is, benzo[1,2-b:4,5-b']-, naphtho[2,3-b:6,7-b']-, and anthra[2,3-b:6,7-b']- difuran, -dithiophene, and -diselenophene. By comparing their electrochemical and photochemical properties, the electronic structures of acenedichalcogenophenes can be expressed as the outcome of balance between the central acene core and the outermost chalcogenophene rings. Among isomerically pure parent anti-anthradichalcogenophenes, anti-ADT and anti-ADS can afford crystalline thin films by vapor deposition, which acted as active layer in organic field-effect transistors with mobility as high as 0.3 cm(2) V(-1) s(-1) for ADT and 0.7 cm(2) V(-1) s(-1) for ADS. The mobility of isomerically pure anti-ADT is higher by several times than those reported for isomercally mixed ADT, implying that the isomeric purity could be beneficial for realizing the better FET mobility. We also tested the diphenyl derivatives of anti-ADF, -ADT, and -ADS as the active material for OFET devices, which showed high mobility of up to 1.3 cm(2) V(-1) s(-1).

[2,2']Bi[naphtho[2,3-b]furanyl] was synthesized, characterized, and examined as an organic semiconductor for thin-film OFETs, bilayer OPVs, and organic light-emitting transistors (OLETs). In the devices, the material acted as a p-type semiconductor, showing moderately high mobility in OFETs, good photo conversion efficiency in OPVs, and blue-green emission in OLETs.

General Synthesis of Dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT)Derivatives. -The method for the preparation of the target compounds is shorter (6 vs. 7 steps) and higher-yielding than that previously reported. It does not require chromatographic separation of the isomeric by-products enabling a scalable synthesis. Semiconducting properties of (IX) are tested. -(NIIMI, K.; KANG, M. J.; MIYAZAKI, E.; OSAKA, I.; TAKIMIYA*, K.; Org. Lett. 13 (2011) 13, 3430-3433, http://dx.doi.org/10.1021/ol2010837 ; Dep. Appl. Chem., Fac. Eng., Hiroshima Univ., Higashi-Hiroshima 739, Japan; Eng.) -R. Steudel 45-094