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We have designed and successfully synthesized star‐shaped oligothiophenes, which could be used as semiconducting materials for solution‐processible organic field‐effect transistors (FETs). By systematically changing the chemical structure of the star‐shaped oligothiophenes we obtained the structural requirements needed for making working FETs from them. UV‐vis fluorescence measurements showed that a molecule of the star‐shaped compounds under consideration is not a fully conjugated molecule, but it has three independently conjugated oligothienyl‐phenylene blocks. A possible scheme of molecular packing of the star‐shaped oligothiophenes in a lamellar structure was proposed and confirmed by atomic force microscopy (AFM) and X‐ray diffraction (XRD) measurements. Although the star‐shaped semiconductors show a somewhat lower mobility than their linear analogs, they possess better solubility and film‐forming properties, leading to improved spin‐coating processing. The best FETs were made by spin‐coating 1,3,5‐tris(5″‐decyl‐2,2′:5′,2″‐terthien‐5‐yl)benzene from a chloroform solution, which resulted in a mobility of 2 × 10–4 cm2 V –1s–1, a 102 on/off ratio at gate voltages of 0 V and –20 V, and a threshold voltage close to 0 V.

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Two novel 2D and 3D coordination polymers of 9,10‐triptycenedicarboxylic acid and zinc nitrate, which form under solvothermal reaction conditions, are described. As determined by single‐crystal X‐ray structure analysis, their frameworks are assembled from dinuclear zinc coordination units which are interlinked by triptycenedicarboxylato (TDC) struts. In the 2D‐MOF reported here, the extended network of van der Waals interactions between triptycene units as well as coordinated solvent molecules is responsible for the dense assembly of layers with a 44 net topology into the final crystal structure. The framework of the 3D‐MOF is composed from [Zn2(TDC)1.5]∞ layers with a 63 topology, the layers being interlinked by triptycenedicarboxylato pillars (bnn‐net). This MOF possesses hexagonal channels which are filled with guest molecules.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

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