The synthesis, property evaluation,a nd single crystal X-ray structures of four 5,7,12,14-tetrafunctionalized diazapentacenes are presented. The synthesis of these compounds either starts from tetrabromo-N,N-dihydrodiazapentacene or from ad iazapentacene tetraketone.P dcatalyzed coupling or addition of al ithiuma cetylide gave the precursors that furnish, after furtherr edox reactions, the diazapentacenes as stable crystalline materials. The performance of the tetraphenyl-substituted compoundas n-channel semiconductor was evaluated in organic field effect transistors.

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We report the synthesis of 5,7,12,14-tetraphenyl-substituted 6,13-dihydro-6,13-diazapentacene and its fully aromatic 6,13-diazapentacene congener. Both arylated diazapentacenes were characterized by X-ray crystallography to investigate their solid-state structures and by UV–vis spectroscopy and cyclic voltammetry to unveil their electronic properties. The experimental results are complemented with theoretical investigations. The semiconductor properties of both diazapentacene derivatives were assessed in organic field-effect transistors, whereby the fully aromatized compound showed comparably less abundant n-type behavior.

The synthesis of a series of unsymmetrical derivatives of pentacene appended with functionalized anthracene moieties is reported. These anthraceneÀ pentacene dyads have been characterized by UV-vis spectroscopy and cyclic voltammetry to examine their electronic properties. X-ray crystallographic analysis was used to examine the solid-state features of anthraceneÀ pentacene dyads 1 a-d with HÀ , FÀ , ClÀ , and BrÀ substituents on the 9-position of anthracene, and shows that the packing arrangement of anthraceneÀ pentacene derivatives 1 b,d,e are remarkably similar irrespective of the presence of fluoride, bromide or methyl substituents. The pentaceneÀ anthracene dyads have been incorporated into OTFTs to evaluate their semiconducting properties. The pentacene derivative 1 b shows ambipolar behavior using AlO x C 14 PA as the gate dielectric (electron and hole mobilities of 7.6 · 10 À 3 and 1.6 · 10 À 1 cm 2 V À 1 s À 1 ), while performance of all derivatives was poor using p-doped Silicon as the substrate. These studies highlight the importance of thin-film formation over molecular structure.