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The extension of the pyrene ring from dimethyl 2,2′-(pyrene-1,6-diyl)dibenzoate derivatives by an intramolecular Friedel–Crafts acylation can be realized in an efficient and regioselective manner using triflic acid as proton source. Naphtho-tetracenone derivatives are obtained in high yields at room temperature while Bis-tetracene-diones are prepared upon heating. Both products display interesting fluorescence properties in the visible range with quantum yields varying from 50 to 60 %.

Diindeno[1,2-b:2′,1′-n]perylene, a new derivative of the indenoacene family was synthesized, and its electronic, electrochemical, and electrical properties were investigated. This material has a closed shell electronic configuration which corresponds to a quinoidal structure with a low band gap of 1.35 eV. Molecular packing in the single crystal was studied by single-crystal X-ray structural analysis, and this information was subsequently used in the determination of the charge transfer integrals via density functional theory methods. The charge-carrier transport properties of the diindeno[1,2-b:2′,1′-n]perylene-5,12-dione and diindeno[1,2-b:2′,1′-n]perylene derivatives were investigated through the fabrication and characterization of field-effect transistors via both vacuum-deposited and solution-processed films, respectively. Diindeno[1,2-b:2′,1′-n]perylene exhibited a field-effect behaviour with a hole mobility up to 1.7 × 10−3 cm2 V−1 s−1 when the active layer was solution-processed.

The benchmark of soluble organic semiconductors based on acenes is the 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS–PEN). However TIPS–PEN still suffers from photoinduced oxidation due to its low degree of aromaticity. Increasing the aromaticity while keeping similar optical and electrochemical properties as well as a shape suitable for good hole transport can be achieved with two-dimensional polycyclic aromatic hydrocarbons (2D-PAHs). Herein, we present an efficient synthesis and characterization of bistetracene derivatives that exhibit a band gap up to 1.71 eV and an increased stability up to 21 times compared to TIPS–PEN and mobility over 0.1 cm2 V−1 s−1 in solution-processed organic field-effect transistors. Based on simple structural consideration, the high stability is attributed to the aromaticity of the bistetracene which is comparable to an anthrancene along each tetracene. According to Clar's sextet rule, the bistetracene should be best regarded as two anthracenes fused at the face bridged by two ethylenic spacers. The synthesis path paves the way towards the preparation of ambipolar and/or longer 2D-PAHs such as bispentacenes and could give rise to organic semiconductors with interesting properties.

Preparations of benzannulated cycloheptanones starting from unique binaphthyl molecular platforms are described. Binaphthyl acetic acids proved suitable percursors for fused cycloheptanone architectures. Seven-membered rings embedded in binaphthyl units were selectively generated by use of Eaton's reagent. Isomeric helical architectures arising from electrophilic cyclisation processes at second reaction sites in the precursors could also be obtained under different acidic conditions. Unambiguous discrimination between isomeric geometries was provided by multiple quantum NMR sequences. DFT calculations were performed and gave evidence of different behaviour of the substrates towards intramolecular electrophilic substitution. The theoretical approach confirmed the experimental results, agreeing completely with X-ray data.

Proline-catalyzed α-amination of a variety of chiral β-hydroxyaldehydes followed by reduction step afforded the corresponding chiral 2-hydrazino-1,3-diols in good yields, enantioselectivities and diastereoselectivities.

A fixed Chichibabin's hydrocarbon CHI1 shows a closed shell configuration with a broad absorption from 400 up to 900 nm., Diindeno[1,2-b:2′,1′-n]perylene, a new derivative of the indenoacene family was synthesized, and its electronic, electrochemical, and electrical properties were investigated. This material has a closed shell electronic configuration which corresponds to a quinoidal structure with a low band gap of 1.35 eV. Molecular packing in the single crystal was studied by single-crystal X-ray structural analysis, and this information was subsequently used in the determination of the charge transfer integrals via density functional theory methods. The charge-carrier transport properties of the diindeno[1,2-b:2′,1′-n]perylene-5,12-dione and diindeno[1,2-b:2′,1′-n]perylene derivatives were investigated through the fabrication and characterization of field-effect transistors via both vacuum-deposited and solution-processed films, respectively. Diindeno[1,2-b:2′,1′-n]perylene exhibited a field-effect behaviour with a hole mobility up to 1.7 × 10–3 cm2 V–1 s–1 when the active layer was solution-processed.

Herein, we report an easy preparation of azide-coated polystyrene-based nanoparticles (15 nm in diameter) and their surface functionalization via CuAAC with fluorophores in water. Resultant dual fluorescent nanoparticles coated with dansyl and pH-sensitive fluorescein moieties as the donor/acceptor FRET pair show a ratiometric response to pH upon excitation at a single wavelength.

The magnetically assisted removal of fatty acids from organic solutions and vegetable oils using iron oxide magnetic nanoparticles (MNPs) was investigated. The effect of contact time and concentration on the adsorption of oleic acid from ethanol–hexane solutions was investigated at room temperature using equilibrium batch experiments. The results showed that the adsorption is rapid (