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.

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.

The highly active, reusable and regioselective crown ethers bases catalytic systems, especially 15‐Crown‐5/NaOH, 18‐Crown‐6/KOH, dibenzo‐18‐Crown/6‐t‐BuOK, and 18‐Crown‐6/t‐BuOK, for double bond migration in various allyl and diallyl compounds have been presented. Allyl and/or diallyl: arenes and heteroarenes, ethers, acetal, sulfides, selenide, sulfoxides, imines, phosphine, and phosphine oxide were smoothly converted into their corresponding 1‐propenyl derivatives under very mild conditions. Some of the C,O‐ and O,S‐diallyl compounds were fully regioselectively isomerized to allyl‐(1‐propenyl) derivatives. An unprecedented and significant effect of increasing the reaction rate and shortening the quantitative reaction conversion time without decreasing the selectivity under ultrasound‐assisted conditions was observed. Various solvents, including low‐boiling point ones containing only C, H and/or O atoms, such as DMFL, DME, THF, Et2O, toluene, and 1,4‐dioxane, can be used instead of the most frequently used DMSO. Remarkably highly effective recycling of 18‐Crown‐6/t‐BuOK and dibenzo‐18‐Crown‐6‐t‐BuOK catalytic systems for isomerization of low‐boiling or high‐boiling point allyl compounds respectively and crown ethers from all examined catalytic systems was developed. The opportunity to effectively combine the double bond migration with in situ generation of nitrile oxide and finally 1,3‐DC‐cycloaddition into one pot variant synthesis of isoxazolines from Qallyl has also been announced.

PAHs (polycyclic aromatics hydrocarbons), the compound group that contains perylene and its derivatives, including functionalized ones, have attracted a great deal of interest in many fields of science and modern technology. This review presents all of the research devoted to modifications of PAHs that are realized via the Diels–Alder (DA) cycloaddition of various dienophiles to the bay regions of PAHs, leading to the π-extension of the starting molecule. This type of annulative π-extension (APEX) strategy has emerged as a powerful and efficient synthetic method for the construction of polycyclic aromatic hydrocarbons and their functionalized derivatives, nanographenes, and π-extended fused heteroarenes. Then, [4 + 2] cycloadditions of ethylenic dienophiles, -N=N-, i.e., diazo-dienophiles and acetylenic dienophiles, are presented. This subject is discussed from the organic synthesis point of view but supported by theoretical calculations. The possible applications of DA cycloaddition to PAH bay regions in various science and technology areas, and the prospects for the development of this synthetic method, are also discussed.