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A class of dialkylamino-substituted dibenzodiazepines and their hetero analogues was synthesized by the intramolecular aza-Wittig condensation of the amido group with iminophosphoranes. The one-pot, two-step procedure includes reductive synthesis of the intermediate iminophosphoranes from the corresponding nitroamides and tributylphosphine.

Arylamine moieties oxidized to radical cations are considered promising spin bearing units in high-spin-type compounds. Here, we report the first use of carbazole-3,6-diamine units as efficient, rigid spin containing units. The use of rigid spin bearing units enhances significantly spin exchange interactions. The design using density functional theory calculations shows the progressive increase of the exchange coupling constant dependent on the considered model molecules. Two of the most representative molecules containing flexible (dimer 1) and rigid spin coupling unit (dimer 2) were synthesized. Electrochemical and pulsed-electron paramagnetic resonance nutation studies showed that both dimers can be oxidized to yield a majority of dicationic diradicals exhibiting S= 1 ground states. The high values of the dimer 2exchange coupling constant obtained both computationally (J/kB= 145 K; HHeis.= −JS1S2) and experimentally (J/kB= 90–100 K) indicate the beneficial role of the carbazole moiety incorporated into spin bearing units.

New, solution processable organic semiconductors, namely arylene bisimides core- or N-functionalized with triarylamines have been synthesized in view of their potential application in organic electronics. In N-functionalized compounds the electrochemically determined oxidation potentials are 0.46 and 0.48 V vs Fc/Fc+for perylene (P1) and naphthalene (N1)bisimides, respectively. For the core functionalized perylene bisimide (P2) this potential is shifted to higher values (0.55 V vs Fc/Fc+). A reversed trend is observed for the first reduction potential since P2is being reduced at the lowest potential (−1.09 V) whereas N1and P1at −1.05 and −1.02 V, respectively. These shifts observed in the case of P2are induced by donor–acceptor interactions between the substituent and the core. The results of DFT calculations performed for N-substituted bisimides indicate a clear separation in space of the HOMO and LUMO orbitals, the former being located on the triarylamine substituent whereas the latter is on the bisimide core. To a first approximation, their UV–vis–NIR spectra can be considered as a superposition of the triarylamine spectrum and those of bisimides containing nonchromophore (alkyl) substituents. This indicates a very weak or essentially nonexistent conjugation between the aromatic core and the N-substituents. In powders, the N-functionalized bisimides show liquid crystalline-type structural organization whereas in thin, spin-coated films they are amorphous. The core-substituted bisimide shows different properties. In this case a new band of a charge transfer (CT) character appears in its UV–vis spectrum. In accordance with the spectroscopic data, the DFT calculations indicate that in the core-substituted compound the HOMO electron density spreads from the triarylamine substituent to the bisimide core. Powders of the core-substituted bisimide crystallize in a 3D structure whereas thin spin-coated films show liquid crystalline-like structural organization. Taking into account their electrochemical properties, all three bisimides studied seem to be good candidates for the fabrication of air operating ambipolar transistors. However, N-functionalized bisimides show only p-type behavior with the hole mobility approaching 10–4cm2V–1s–1in the all organic (CYTOP dielectric) field effect transistor configuration. The core-substituted bisimide shows, however, the expected ambipolar behavior with the hole and electron mobilities of 1.5 × 10–3and 3.5 × 10–4cm2V–1s–1, respectively.

A facile synthetic method involving SNAr coupling of 4-fluoronitrobenzene to arylamines, followed by reduction of the nitro groups, has been developed. The method allows the preparation of symmetric NH2NH2end-capped and asymmetric PhNH2end-capped oligoanilines of even or odd chain lengths. The preparation of the NH2NH2end-capped trimer to octamer and PhNH2end-capped trimer to pentamer is described. The effect of the chain length on the spectroscopic properties of the oxidized oligomers has been investigated by UV-Vis-NIR spectroscopy.

A new synthetic method involving SNAr coupling of 4-fluoronitrobenzene to arylamines, followed by the reduction of the nitro groups, has been developed. Two types of aniline oligomers, namely PhNH2and NH2NH2tetramers have been prepared by this method. Tetramers in the leucoemeraldine and in the emeraldine oxidation states were characterized by NMR, UV-Vis-NIR, IR and mass spectroscopies. It shown that the NH2NH2tetramer oxidized to the emeraldine state forms two isomers: syn and anti. The oxidation of the PhNH2tetramer leads to the creation of positional isomers, depending on the synthetic method.

A facile synthetic method involving S_NAr coupling of 4-fluoronitrobenzene to arylamines, followed by reduction of the nitro groups, has been developed. The method allows the preparation of symmetric (NH₂/NH₂ end-capped) and asymmetric (Ph/NH₂ end-capped) oligoanilines of even or odd chain lengths. The preparation of the NH₂/NH₂ end-capped trimer to octamer and Ph/NH₂ end-capped trimer to pentamer is described. The effect of the chain length on the spectroscopic properties of the oxidized oligomers has been investigated by UV-Vis-NIR spectroscopy.

A new synthetic method involving S_NAr coupling of 4-fluoronitrobenzene to arylamines, followed by the reduction of the nitro groups, has been developed. Two types of aniline oligomers, namely Ph/NH₂ and NH₂/NH₂ tetramers have been prepared by this method. Tetramers in the leucoemeraldine and in the emeraldine oxidation states were characterized by NMR, UV-Vis-NIR, IR and mass spectroscopies. It shown that the NH₂/NH₂ tetramer oxidized to the emeraldine state forms two isomers: syn and anti. The oxidation of the Ph/NH₂ tetramer leads to the creation of positional isomers, depending on the synthetic method.

AbstractNew polythiophene derivatives containing azo dye side group were prepared via copolymerization of 3-alkylthiophenes and Disperse Red 1 substituted thiophenes. The presence of chromophore groups in the polymers was confirmed by NMR and FTIR spectroscopies as well as by elemental analysis. The obtained soluble polymers were processed into thin films by spin coating technique and their nonlinear optical properties were studied by the optical second harmonic generation technique and by quadratic electro-optic Kerr effect. The second order nonlinear optical coefficients are : dsp= 6.8 pm/V and dpp= 28.3 pm/V at 1064 nm fundamental wavelength. The quadratic electro-optic Kerr coefficient is about three times larger for the unfunctionalized polymer than for unfoncionalized.

Polyaniline (PANI) protonated with camphorsulfonic acid (CSA) and three different poly(alkylene phosphates) (PAPs) (where alkylene = pentylene, hexylene, or nonylene) was used in the fabrication of conductive polyaniline–poly(methyl methacrylate) (PMMA) blends. The lowest percolation threshold (fp = 0.041 wt %) was obtained for the PANI(CSA)0.5–PMMA blend plasticized with 35 wt % of dibutyl phtalate (DBPh). This blend is also very resistant against the deprotonation of its conductive phase in basic solutions of pH = 9. In the case of blends prepared with the use of PAPs as PANI dopants, the percolation threshold strongly depends on the length of the hydrophobic spacer (alkylene group) in the dopant. The percolation threshold decreases in the order PPP > PHP > PNP, whereas the resistance against deprotonation in basic solutions decreases in the following inverse order: PNP > PHP > PPP. This last observation can be rationalized by increasing contribution of hydrophobic segments in the polymeric dopant, when going from PPP to PNP, which renders polyaniline more resistance toward the penetration by aqueous basic solutions. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 471–479, 1999