Halogenated azobenzene acrylates: from efficient solution photoswitching to stable solid-state photochromic materials

• Martina Vachtlová,
• Michaela Fecková,
• Vítězslav Zima,
• Jan Podlesný,
• Milan Klikar,
• Oldřich Pytela,
• Patrik Pařík,
• Jakub Opršal,
• Eliška Juhaňáková,
• Veronika Chrtová and
• Filip Bureš

Beilstein J. Org. Chem. 2026, 22, 782–794, doi:10.3762/bjoc.22.60

• ; photoswitch; polymer; thin film; Introduction The azobenzene photoinduced E/Z isomerization represents a well-investigated switching process that found various utilizations [1][2][3][4]. In contrast to the state-of-the-art achieved in solution and despite its perhaps even greater application potential, a

• compound 1e obtained by UV–vis monitoring at c = 4 × 10−5 M (DCE, 60 °C). B) Thermal kinetics curve of compound 1e obtained by 1H NMR monitoring (CDCl3, 60 °C). Photoswitching of target azobenzene 1a in the solid state (polymeric matrix). A) Polystyrene thin film partly irradiated with 355 nm for 2 hours

• . B) Polystyrene thin film partly irradiated with 355 nm after 20 days in the dark at 22 °C. C) Polystyrene thin film partly irradiated with 355 nm after 40 days in the dark at 22 °C. D) Polystyrene thin film partly irradiated with 355 nm after 90 days in the dark at 22 °C. E) UV–vis absorption

Advances in Zr-mediated radical transformations and applications to total synthesis

• Hiroshige Ogawa and
• Hugh Nakamura

Beilstein J. Org. Chem. 2026, 22, 71–87, doi:10.3762/bjoc.22.3

• where organic synthesis plays a central role, including pharmaceuticals, agrochemicals, materials chemistry, organic semiconductors, and organic thin-film solar cells. These areas are intimately linked to human life; thus, advances in organic synthesis are essential for improving human well-being

Highly distinguishable isomeric states of a tripodal arylazopyrazole derivative on graphite through electron/hole-induced switching at ambient conditions

• Himani Malik,
• Sudha Devi,
• Debapriya Gupta,
• Ankit Kumar Gaur,
• Sugumar Venkataramani and
• Thiruvancheril G. Gopakumar

Beilstein J. Org. Chem. 2025, 21, 1496–1507, doi:10.3762/bjoc.21.112

• their importance in exploring novel and thermally less stable molecular switches. Results and Discussion Typical AFM phase images of an ultra-thin film of FNAAP deposited from ethanolic solution on highly oriented pyrolytic graphite (HOPG) are shown in Figure 2. The corresponding topographs are shown in

• Supporting Information File 1. The AFM images of the ultra-thin film reveal domains of assembled molecules shown as bright contrast, marked by green and yellow dashed lines in Figure 2a,b. The pristine graphite surface has a median contrast. The molecular domains are growing as long islands with well-defined

• visible in large-area STM images as well. A super-periodic pattern is visible at low resolution, and the periodicity (≈6.1 nm) matches with the AFM measurements. Additional STM images of the ultra-thin film of FNAAP at different resolutions are provided in Supporting Information File 1, section 5. Next

Recent advances and future challenges in the bottom-up synthesis of azulene-embedded nanographenes

• Bartłomiej Pigulski

Beilstein J. Org. Chem. 2025, 21, 1272–1305, doi:10.3762/bjoc.21.99

• 153. The nanoribbon is soluble in common organic solvents and exhibits conductivity values up to 1.5∙10−3 S∙cm−1 when doped by TFA in the thin film state. The serendipitous synthesis of azulene-embedded [5]helicenes was reported by Usui, Suemune, and co-workers [99]. The unexpected formation of an

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

• Yang Chen,
• Jiao He,
• Hang Lin,
• Hai-Feng Wang,
• Ping Hu,
• Bi-Qin Wang,
• Ke-Qing Zhao and
• Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

• fluorescence emission spectroscopies reveal green photoluminescence with fluorescence quantum yields of up to 33% for the Fn derivatives. The J-aggregation for the inner fluorine-substituted dimers Gnm is energetically and stereoelectronically more favorable and G66 exhibits thin-film fluorescence with a large

• been studied in various solutions and thin film: G66 emitted green light in solution with an absolute photoluminescent quantum yield of ca. 33%. Results and Discussion Synthesis and characterization We have recently generalized a very efficient “palladium-free” synthesis for the preparation of a

• . Photophysical properties: UV–vis absorption and photoluminescence UV–vis absorption and fluorescence spectra of the synthesized fluorine polycyclic aromatic hydrocarbons Fn and Gnm were measured in solution (in various solvents) and thin film and the results are summarized in Figure 6 and Table S7 in Supporting

Interaction of a pyrene derivative with cationic [60]fullerene in phospholipid membranes and its effects on photodynamic actions

• Hayato Takagi,
• Çetin Çelik,
• Ryosuke Fukuda,
• Qi Guo,
• Tomohiro Higashino,
• Hiroshi Imahori,
• Yoko Yamakoshi and
• Tatsuya Murakami

Beilstein J. Org. Chem. 2024, 20, 2732–2738, doi:10.3762/bjoc.20.231

• the photocontrol of the plasma membrane potential (Vm) using fullerene-containing triad molecules on a millisecond scale. Experimental Preparation of liposomes with catC60 (catC60-lip) or C60 (C60-lip) Liposomes were prepared using a thin-film hydration method. DMPC (NOF AMERICA Corporation, White

Photoluminescence color-tuning with polymer-dispersed fluorescent films containing two fluorinated diphenylacetylene-type fluorophores

• Kazuki Kobayashi,
• Shigeyuki Yamada,
• Motohiro Yasui and
• Tsutomu Konno

Beilstein J. Org. Chem. 2024, 20, 2682–2690, doi:10.3762/bjoc.20.225

• Fabrication of PMMA dispersion films PMMA films containing one of two fluorinated diphenylacetylenes were prepared using an Opticoat MS-B100 spin coater (MIKASA, Japan). The mother liquor for the thin-film deposition was prepared as follows: it was mounted on a thoroughly cleaned glass slide and clamped to

Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels

• Connor R. M. MacDonald and
• Emily R. Draper

Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220

• which is not necessarily the same as the bulk morphology. Cryo-TEM can better probe three-dimensional structures, however, it is important to consider the additional artifacts that arise in cryo-TEM sample preparation. Cryo-TEM requires a thin film sample which can be difficult to prepare with a gel

Novel truxene-based dipyrromethanes (DPMs): synthesis, spectroscopic characterization and photophysical properties

• Shakeel Alvi and
• Rashid Ali

Beilstein J. Org. Chem. 2024, 20, 2163–2170, doi:10.3762/bjoc.20.186

• ][12][13]. The most promising applications of truxene-based systems have been found in organic photovoltaics (OPVs), dye‐sensitized solar cells (DSSCs), fluorescent probes, organic thin‐film transistors (OTFTs), lasers, organic light emitting diodes (OLEDs), liquid crystals, non-linear optical (NLO

Synthesis and characterization of 1,2,3,4-naphthalene and anthracene diimides

• Adam D. Bass,
• Daniela Castellanos,
• Xavier A. Calicdan and
• Dennis D. Cao

Beilstein J. Org. Chem. 2024, 20, 1767–1772, doi:10.3762/bjoc.20.155

• organic thin-film transistors from heteroacenes. Inspired by these results, we sought to demonstrate the preparation of all-carbon scaffolds, i.e., acenes, that are cata-annulated with cyclic imides. Here, we communicate the successful synthesis of 1,2,3,4-NDIs and -ADIs and the characterization of their

Two-fold addition reaction of silylene to C₆₀: structural and electronic properties of a bis-adduct

• Masahiro Kako,
• Masato Kai,
• Masanori Yasui,
• Michio Yamada,
• Yutaka Maeda and
• Takeshi Akasaka

Beilstein J. Org. Chem. 2024, 20, 1179–1188, doi:10.3762/bjoc.20.100

• with excellent properties as organic photovoltaic materials [9][10][11][12][13][14]. Furthermore, regioisomerically pure bis-functionalized fullerenes function better as electron acceptors in organic thin-film solar cells than mixtures of the corresponding regioisomers do [12][13][14]. Therefore

Kinetically stabilized 1,3-diarylisobenzofurans and the possibility of preparing large, persistent isoacenofurans with unusually small HOMO–LUMO gaps

• Qian Liu and
• Glen P. Miller

Beilstein J. Org. Chem. 2024, 20, 1099–1110, doi:10.3762/bjoc.20.97

• (see Supporting Information File 1). The mesityl and 2’,4’,6’-triethylphenyl substituents both provide a strong measure of kinetic stabilization. Solution phase stability is particularly important if isoacenofurans are to be utilized as thin-film organic semiconductors cast from solution. Conclusion We

Structure–property relationships in dicyanopyrazinoquinoxalines and their hydrogen-bonding-capable dihydropyrazinoquinoxalinedione derivatives

• Tural N. Akhmedov,
• Ajeet Kumar,
• Daken J. Starkenburg,
• Kyle J. Chesney,
• Khalil A. Abboud,
• Novruz G. Akhmedov,
• Jiangeng Xue and
• Ronald K. Castellano

Beilstein J. Org. Chem. 2024, 20, 1037–1052, doi:10.3762/bjoc.20.92

• both n- and p-type organic semiconductors [9][10][11][12]. The Würthner and Meijer groups presented an early example of the utility of hydrogen bonding in the fabrication of organic semiconductor devices. A thin-film device architecture was developed consisting of oligo(p-phenylenevinylene) (OPV) and

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• introduced by Herwig and Müllen as early as in 1996 for pentacene, which was ultimately obtained in a thin-film by a thermally-activated retro-Diels–Alder reaction from a tailor-made tetrachlorobenzene-pentacene soluble adduct (Scheme 1, top left) [13][14]. Over the years, thermally-induced

• concept, a thin-film of the latter sulfoxide precursor, spin-coated onto a glass sample, yielded full conversion to PBI 6a in only 2 min, confirming the potential application of this precursor in electronic devices. Light irradiation was next tested as an alternative activation method, since

• reactive as a thin-film on a glass substrate, with the generation of the desired perylene upon photoirradiation with a blue LED (λ = 470 nm) [62]. Finally, cooperativity of light and heat was demonstrated on a crystalline sample of sulfoxide 4a, where photoirradiation enhanced the SO-extrusion process at

Optimizing reaction conditions for the light-driven hydrogen evolution in a loop photoreactor

• Pengcheng Li,
• Daniel Kowalczyk,
• Johannes Liessem,
• Mohamed M. Elnagar,
• Dariusz Mitoraj,
• Radim Beranek and
• Dirk Ziegenbalg

Beilstein J. Org. Chem. 2024, 20, 74–91, doi:10.3762/bjoc.20.9

• voltage of 15 kV. To prepare the sample for SEM imaging, a few milligrams of the Pt-PCN material were dispersed in 1.0 mL of ethanol using sonication for 5 min. Subsequently, a thin film of the sample was obtained by drop-casting a few microliters of the suspended sample onto a conductive Cu foil

Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio

• Keiko Kojima,
• Nodoka Kosugi,
• Hirokuni Jintoku,
• Kazufumi Kobashi and
• Toshiya Okazaki

Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7

• increases with larger L/D ratios of the SWCNTs [23]. The findings in this study align with these previous results, as the tactoid transition volume and DWCNT aspect ratio were larger compared to previous SWCNT-SC dispersions [23]. A thin film was produced utilizing a bar-coating method with DWCNT LC

• flowing air (200 mL/min) at a ramping rate of 1 °C/min. The Raman and absorption spectra were obtained from DWCNT thin film on a silicon substrate. The DWCNT thin film was prepared using vacuum filtration. Raman measurements were conducted using a HORIBA T64000 532 nm laser, while far-infrared (FIR

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• the energy required to remove an electron from a solid material. Thin film samples were precisely prepared through vacuum deposition onto cleaned fluorine-doped tin oxide (FTO)-coated glass substrates, maintained at a low pressure of 2 × 10−6 mbar to ensure sample integrity. During the IPPE experiment

Thienothiophene-based organic light-emitting diode: synthesis, photophysical properties and application

• Recep Isci and
• Turan Ozturk

Beilstein J. Org. Chem. 2023, 19, 1849–1857, doi:10.3762/bjoc.19.137

• many applications such as OLEDs, micro-LEDs, LCDs, lasers, and photodiodes by applying thin film methods and solution processes [5][6][7][8]. The performance of organic electronics is based on the active layer composition as well as the fabrication methods and processing parameters. The organic active

Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• copolymer, benzodithiophene-thiadiazolo-quinoxaline (Qx54), by introducing trifluoromethyl groups to the Qx moiety (Qx55). This strategic modification changed the HOMO and LUMO levels, resulting in a conversion from ambipolar charge transport to n-type charge transport. The polymeric thin-film transistors

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• , thin film, and solid powder. As shown in Figure 2a, the UV–vis absorption spectrum in diluted toluene solution displays intense absorption peaks in the high energy region (<380 nm) and a much weaker absorption peak at 508 nm attributed to the π–π* transition of the conjugated aromatic backbone and

• . TPECNz in thin film and solid powder also displayed deep-red emission observed by PL maxima at 668 and 665 nm, respectively (Figure 2b). As listed in Table 1, the TPECNz solution shows an excellent absolute PL quantum yield (PLQY) of 96%, whereas the spin-coated thin film exhibits a red-shifted spectrum

• simple mix-up of the two states [56]. Furthermore, to further understand the PLQY of the molecule in solution and thin film, the radiative rate constant (kr) and non-radiative rate constant (knr) were calculated from the PLQY values and PL lifetimes (τ) according to Equation 1 and Equation 2. As can be

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• they can be easily structurally characterized, have highly reproducible syntheses, and can exhibit high solubilities in common organic solvents for effective solution processing and thin film formation. Towards obtaining high-performance CIL materials, perylene diimides (PDIs) stand out as excellent

• are reported for the design strategy used, their synthesis, optoelectronic properties, electrochemical properties, and processability from ethyl acetate for thin film formation. Lastly, each new CIL material was tested in conventional OPVs by processing with ethyl acetate, a green solvent [20][21][22

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

Phenanthridine–pyrene conjugates as fluorescent probes for DNA/RNA and an inactive mutant of dipeptidyl peptidase enzyme

• Josipa Matić,
• Tana Tandarić,
• Marijana Radić Stojković,
• Filip Šupljika,
• Zrinka Karačić,
• Ana Tomašić Paić,
• Lucija Horvat,
• Robert Vianello and
• Lidija-Marija Tumir

Beilstein J. Org. Chem. 2023, 19, 550–565, doi:10.3762/bjoc.19.40

• applications [9]. These compounds have a very large aromatic surface suitable to form self-assembled supramolecular structures by intermolecular π–π interactions and showed excimer fluorescence in thin film and in the solid state. Kawai et al. reported exciplex formation between pyrene and guanine in polar

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• light-absorbance properties. They found their application in material science, where they are used in developing organic photovoltaic prototypes as potential dichroic dyes and organic thin-film transistors. However, due to strong π-stacking interaction, these compounds are not readily soluble, and the

Ionic multiresonant thermally activated delayed fluorescence emitters for light emitting electrochemical cells

• Merve Karaman,
• Abhishek Kumar Gupta,
• Subeesh Madayanad Suresh,
• Tomas Matulaitis,
• Lorenzo Mardegan,
• Daniel Tordera,
• Henk J. Bolink,
• Sen Wu,
• Stuart Warriner,
• Ifor D. Samuel and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2022, 18, 1311–1321, doi:10.3762/bjoc.18.136

• fluorescence; Introduction Light-emitting electrochemical cells (LEECs) are thin film light-emitting devices typically consisting of an emissive layer containing ionic species that facilitate charge transport and an emissive semiconductor material. The emissive layer is sandwiched between two air-stable

• -OBuIm possesses a ΔEST of 0.25 eV. Unfortunately, DiKTa-DPA-OBuIm was insoluble in 2-MeTHF and so the measurement could not be made. No delayed component was observed in MeCN solution under vacuum for either of the compounds (Figure S27 in Supporting Information File 1). The thin film PL behavior of