Five novel derivatives of pyrene, substituted at positions 1,3,6,8 with 4-(2,2-dimethylpropyloxy)pyridine (P1), 4-decyloxypyridine (P2), 4-pentylpyridine (P3), 1-decyl-1,2,3-triazole (P4), and 1-benzyl-1,2,3-triazole (P5), are obtained through a Suzuki-Miyaura cross-coupling reaction or Cu -catalyzed 1,3-dipolar cycloaddition reaction, respectively, and characterized thoroughly. TGA measurements reveal the high thermal stability of the compounds. Pyrene derivatives P1-P5 all show photoluminescence (PL) quantum yields (Φ) of approximately 75 % in solution. Solid-state photo- and electroluminescence characteristics of selected compounds as organic light-emitting diodes are tested. In the guest-host configuration, two matrixes, that is, poly(N-vinylcarbazole) (PVK) and a binary matrix consisting of PVK and 2-tert-butylphenyl-5-biphenyl-1,3,4-oxadiazole (PBD) (50:50 wt %), are applied. The diodes show red, green, or blue electroluminescence, depending on both the compound chemical structure and the actual device architecture. In addition, theoretical studies (DFT and TD-DFT) provide a deeper understanding of the experimental results.

New catalytically or high pressure activated reactions and routes, including coupling, double bond migration in allylic systems, and various types of cycloaddition and dihydroamination have been used for the synthesis of novel bithiophene derivatives. Thanks to the abovementioned reactions and routes combined with non-catalytic ones, new OPEN ACCESSMolecules 2015, 20 4566 acetylene, butadiyne, isoxazole, 1,2,3-triazole, pyrrole, benzene, and fluoranthene derivatives with one, two or six bithiophenyl moieties have been obtained. Basic sources of crucial substrates which include bithiophene motif for catalytic reactions were 2,2'-bithiophene, gaseous acetylene and 1,3-butadiyne.

New D-π-D-π-A low-molecular-weight compounds, based on a phenothiazine scaffold linked via an acetylene unit with various donor moiety and cyanoacrylic acid anchoring groups, respectively, were successfully synthesized. The prepared phenothiazine dyes were entirely characterized using nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. The compounds were designed to study the relationship between end-capping donor groups’ structure on their optoelectronic and thermal properties as well as the dye-sensitized solar cells’ performance. The effect of π-conjugation enlargement by incorporation of different heterocyclic substituents possessing various electron–donor affinities was systematically experimentally and theoretically examined. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations were implemented to determine the electronic properties of the novel molecules.

Diels–Alder cycloaddition of various dienophiles to the bay region of polycyclic aromatic hydrocarbons (PAHs) is a particularly effective and useful tool for the modification of the structure of PAHs and thereby their final properties. The Diels–Alder cycloaddition belongs to the single‐step annulative π‐extension (APEX) reactions and represents the maximum in synthetic efficiency for the constructions of π‐extended PAHs including functionalised ones, nanographenes, and π‐extended fused heteroarenes. Herein we report new applications of the APEX strategy for the synthesis of derivatives of 1,2‐diarylbenzo[ghi]perylene, 1,2‐diarylbenzo[ghi]perylenebisimide and 1,2‐disubstituted‐benzo[j]coronene. Namely, the so far unknown cycloaddition of 1,2‐diarylacetylenes into the perylene and perylenebisimide bay regions was used. 1,2‐Disubstituted‐benzo[j]coronenes were obtained via cycloaddition of benzyne into 1,2‐diarylbenzo[ghi]perylenes by using a new highly effective system for benzyne generation and/or high pressure conditions. Moreover, we report an unprecedented Diels–Alder cycloaddition–cycloaromatisation domino‐type reaction between 1,4‐(9,9‐dialkylfluoren‐3‐yl)‐1,3‐butadiynes and perylene. The obtained diaryl‐substituted core‐extended PAHs were characterised by DFT calculation as well as electrochemical and spectroscopic measurements.

Novel symmetrical anthracene derivatives with bulky carbazolyl‐fluorene, diphenylamino‐fluorene, or carbazolyl‐carbazole units connected to the anthracene frame through an ethynyl bridge were synthesized in excellent yield by using Sonogashira cross‐coupling. The ethynyl bridge in the anthracene dyes increases π‐electron conjugation and the bulky substituents considerably attenuate intermolecular interactions. The dyes possess high thermal stability, tremendous solubility in common organic solvents, and especially high photoluminescence quantum yield (Φf) in solution in the range of 77–98 %. OLED devices were fabricated. The AFM images of thin films and blends prepared from all compounds show a uniform and flat surface, indicating excellent film‐forming properties. Devices incorporating the anthracene derivative with diphenylamino‐fluorene end‐capping groups exhibited the highest value of current density (J). All of the fabricated OLED devices emitted yellowish‐orange light under applied voltage.