Herein we present a synthetic gram-scale route to 5,6:11,8), which is a member of the class of cyclopenta-fused polycyclic aromatic hydrocarbons (CP-PAHs). Full analytical characterization of the title compound was carried out by IR, Raman, UV/Vis, and high-field 1 H NMR spectroscopy, as well as by mass spectrometry. A unique double-elimination of phenylide moieties, as the key reaction step, gave DOPT for the first time in high purity and

The molecular structure of the hydrocarbon 5,6;11,12-di-o-phenylenetetracene (DOPT), its material characterization and evaluation of electronic properties is reported for the first time.Asingle-crystal X-rays tudy reveals two different motifs of intramolecular overlap with herringbonetype arrangement displaying either face-to-edge or co-facial face-to-face packing depicting intensive p-p interactions. Density functional theory (DFT) calculations underpin that afavorable electronic transport mechanism occurs by acharge hopping process due to a p-bond overlap in the DOPT polymorph with co-facial arene orientation. The performance of polycrystalline DOPT films as active organic semiconducting layer in as tate-of-the-art organic field effect transistor (OFET) device was evaluated and proves to be film thickness dependent. For4 0nml ayer thickness it displays as aturation hole mobility (m hole)o fu pt o0 .01 cm 2 V À1 s À1 and an on/offratio (I on /I off)o f1.5 10 3 .

Herein, we report the synthesis and molecular structure of the mono- and dianionic aromatic molecules [(B15C5-κ5O)2K+](LDOPT˙-) (1) and [(B15C5-κ5O)2K+]2(LDOPT2-)THFsolv (2) derived from the parent aromatic polyhydrocarbon 5,6:11,12-di-o-phenylenetetracene (DOPT, LDOPT) by a controlled stepwise one and two electron chemical reduction. The effect of single and double electron charge transfer to a polycondensed aromatic hydrocarbon (PAH) without any disturbing influence of an associated metal cation has been demonstrated. This was achieved by fully sandwiching the cationic K+ counterions between two benzo-15-crown-5-ether (B15C5) ligands resulting in a fully encapsulating (κ10O) geometry which ensures a complete separation of the K+ counterions and the bare anionic PAH species [LDOPT˙-] and [LDOPT2-]. The structural changes accompanied by the stepwise reduction from LDOPT to [LDOPT˙-] to [LDOPT2-] are discussed and compared to earlier predictions based on density functional theory (DFT) as well as the results of previous studies of alkaline metal cationic PAH anion interactions of DOPT in which only a partial metal cation encapsulation has been achieved so far.

Twofold reduction of the title molecule 5,6;11,12-di-o-phenylenetetracene (DOPT) with an excess of metallic rubidium and cesium in the presence of strongly coordinating ethers like 18-crown-6-ether (18C6) and tetraglyme results in the formation of the first Rb(i) triple-decker complex and the first Cs(i) coordination polymer of the so far only sparsely studied polyaromatic planar hydrocarbon DOPT. Both compounds are extremely sensitive towards air and water in solution as well as in the solid state. Both compounds exhibit isomerism within their crystal lattices.

Herein we report the synthesis and crystal structures of three light alkali metal salts of the dianion of the polycyclic aromatic hydrocarbon 5,6:11,12-di-o-phenylenetetracene (L). The compounds are obtained by reaction of L with an excess of lithium or sodium metal in different O-donor solvents (DME, diglyme) and crystallize as naked, solvated-cation separated dianions exhibiting no interaction between the alkali metal ion and the aromatic π-system of L. Depending on the aprotic etheral solvent and the hardness of the alkaline metal agent a significant structural perturbation of the conjugated carbon framework of L is observed resulting in a bowl shaped curvature of the anionic π-perimeter, in contrast to its fully planar neutral state. Reduction of L with lithium in DME results in the formation of the solvent-separated molecular structure of {[(DME-κO)Li](L)}1 containing naked isolated units of dianionic L. A similar structural arrangement is observed for the corresponding sodium compound {[(DME-κO)Na](L)}2 in which, however, a lesser curvature of the isolated dianionic ligand skeleton compared to 1 is observed. In contrast to 1 and 2 reduction with sodium in diglyme results in the formation of {[(diglyme-κO)Na](L)}3. The deformation of the peripheric phenylene rings of [L] in 3 is not as pronounced as compared to 1 and 2. Nevertheless, molecular structures of 1-3 deviate from full-planarity as observed in the parent neutral L. No preferential endo- or exo-site coordination of the alkaline metal cations Li and Na on the curved dianionic π-perimeter is observed.

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The molecular structure of the hydrocarbon 5,6;11,12-di-o-phenylenetetracene (DOPT), its material characterization and evaluation of electronic properties is reported for the first time.Asingle-crystal X-rays tudy reveals two different motifs of intramolecular overlap with herringbonetype arrangement displaying either face-to-edge or co-facial face-to-face packing depicting intensive p-p interactions. Density functional theory (DFT) calculations underpin that afavorable electronic transport mechanism occurs by acharge hopping process due to a p-bond overlap in the DOPT polymorph with co-facial arene orientation. The performance of polycrystalline DOPT films as active organic semiconducting layer in as tate-of-the-art organic field effect transistor (OFET) device was evaluated and proves to be film thickness dependent. For4 0nml ayer thickness it displays as aturation hole mobility (m hole )o fu pt o0 .01 cm 2 V À1 s À1 and an on/offratio (I on /I off )o f1.5 10 3 .The carbon framework in the title molecule is found as abasic structural motif in the fullerene molecules C 78 ,C 82 and C 84 (Figure 1). In addition, other symmetrical geodesic fullerene isomers bearing isolated pentagonal ring structures display molecular units of this conjugated polycycle. 5,6;11,12-di-o-phenylenetetracene (DOPT; 2)b elongs to the class of tetracene derivatives which have spurred interest over the last decade as model compounds with respect to an understanding of their chemistry as well as of their electronic properties like electronic structure and charge transport ability. [1,2] In the group of cyclo-pentafused polycyclica romatic hydrocarbons (PAH) 2 represents aprototypical acene framework molecule with peri-substitution closely related to tetracene,5,6,11,12-tetraphenyltetracenerubrene,orthe di-ophenylene substituted anthracene molecule rubicene. [2] Although, reported earlier in elusive experimental work [3] it was only very recently,that DOPT 2 was made accessible by Murata [4] and our group [5] in two independent and straightforward high yield synthetic approaches.Murata et al. presented ag eneral approach towards cyclo-pentafused polycyclic aromatics including DOPT-derivatives starting from the 5,11-diaryl-tetracene framework.[4] Shortly after,w ew ere able to devise agram-scale synthesis based on well established Diels-Alder chemistry for the parent molecule DOPT introducing as of ar unprecedented reductive double phenyl elimination.[5] Highly condensed PA Hm olecules like DOPT with their oftentimes energetically favorable molecular orbital ordering with small electronic band gap differences excel themselves as promising semiconducting organic materials for controlled charge transport. Thea fore mentioned close structural relationship of DOPT to the polyacene aromatic family especially the parent tetracene might promise interesting functional properties applicable in organic electronics like thin film transistors or future solar energy harvesting devices. [6] From asynthetic point of view the acene molecule DOPT i...

Carbon nanofibers with an amorphous solid structure have been synthesized by thermal conversion of the polycyclic aromatic hydrocarbon 5,6;11,12-di-o-phenylenetetracene (DOPT) at 1000 C on various substrates. Rapid annealing of DOPT on copper foil, SiO 2 /Si wafer and a SiO 2 /Si wafer coated with a 20 nm thick layer of Pt/Pd resulted in growth of carbon nanofibers. The most effective synthesis of these fibers was realized on the latter substrate. The Pt/Pd layer segregates by dewetting under thermal treatment and forms metallic nanoparticles on which dense networks of amorphous carbon nanofibers were prepared and these were successfully applied in chemiresistor gas sensor applications for detection of toxic gases, e.g. nitrogen dioxide, ammonia and sulfur dioxide. Using an analyte concentration of parts per million, the nanofibers show a very good response towards NO 2 and SO 2 , whereas exposure to ammonia resulted only in negligible, minor changes in the electrical resistance of the sensor.