Photomechanochemistry: harnessing mechanical forces to enhance photochemical reactions

• Francesco Mele,
• Ana M. Constantin,
• Andrea Porcheddu,
• Raimondo Maggi,
• Giovanni Maestri,
• Nicola Della Ca’ and
• Luca Capaldo

Beilstein J. Org. Chem. 2025, 21, 458–472, doi:10.3762/bjoc.21.33

• (5 mol %) was irradiated with green light while being milled in a 25 mL PMMA milling jar with 15 ZrO2 balls of 5 mm in diameter at 25 Hz. The expected product 8.2 was obtained in 68% yield after isolation. A comprehensive set of control experiments highlighted the essential role of mechanochemistry

Antibiofilm and cytotoxic metabolites from the entomopathogenic fungus Samsoniella aurantia

• Rita Toshe,
• Syeda J. Khalid,
• Blondelle Matio Kemkuignou,
• Esteban Charria-Girón,
• Paul Eckhardt,
• Birthe Sandargo,
• Kunlapat Nuchthien,
• J. Jennifer Luangsa-ard,
• Till Opatz,
• Hedda Schrey,
• Sherif S. Ebada and
• Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 327–339, doi:10.3762/bjoc.21.23

• isolated from a lepidopteran larva found on the leaf litter buried in the soil, on October 6, 2012. Cultivation and extraction Samsoniella aurantia was cultivated on potato dextrose agar (PDA: 200 g potato, 20 g dextrose, 15 g agar in 1 L distilled water, Difco). Mycelial plugs, each with a diameter of 7.0

Three-component reactions of conjugated dienes, CH acids and formaldehyde under diffusion mixing conditions

• Dmitry E. Shybanov,
• Maxim E. Kukushkin,
• Eugene V. Babaev,
• Nikolai V. Zyk and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 262–269, doi:10.3762/bjoc.21.18

• (1 equiv), 0.05 mmol ʟ-proline and 2.0–5.0 mmol diene (2–5 equiv) in 3–5 mL acetonitrile was placed into a 15 mL vial (diameter 1.3 cm). This vial was then placed into a closed 50 mL vial (diameter 2.8 cm) containing 3–5 mL of formalin, and the reaction mixture was stirred at room temperature for 2

Hydrogen-bonded macrocycle-mediated dimerization for orthogonal supramolecular polymerization

• Wentao Yu,
• Zhiyao Yang,
• Chengkan Yu,
• Xiaowei Li and
• Lihua Yuan

Beilstein J. Org. Chem. 2025, 21, 179–188, doi:10.3762/bjoc.21.10

• , when G2 and zinc salt were mixed together in a 1:1 molar ratio, results from dynamic light scattering experiments showed that the average hydrodynamic diameter (Dh) was 524 nm, and no particles of discernible size were observed for a mixture of the macrocycle H1 and G2, or H1 and the salt, whereas with

Mechanochemical difluoromethylations of ketones

• Jinbo Ke,
• Pit van Bonn and
• Carsten Bolm

Beilstein J. Org. Chem. 2024, 20, 2799–2805, doi:10.3762/bjoc.20.235

• , entry 1). The reaction was conducted in a PTFE milling equipment with two milling balls (diameter: 10 mm). Changing to a heavier milling ball (diameter: 15 mm) resulted in a yield of 67% of 3a (Table 1, entry 2). Stopping the reaction after 60 min gave product 3a in 72% yield (Table 1, entry 3). At a

C–C Coupling in sterically demanding porphyrin environments

• Liam Cribbin,
• Brendan Twamley,
• Nicolae Buga,
• John E. O’ Brien,
• Raphael Bühler,
• Roland A. Fischer and
• Mathias O. Senge

Beilstein J. Org. Chem. 2024, 20, 2784–2798, doi:10.3762/bjoc.20.234

• interesting crystal packing features were that observed in the structures of compound 27 and borylated porphyrin 46. In the case of porphyrin 27, when crystallized by slow evaporation from CDCl3, a crystal structure with a void diameter of approximately 5.8 Å was obtained (Figure 4). The void was measured

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

• catC60 and PyBA from the membranes. ESR measurements for photoinduced 1O2 and O2•– generation ESR spectra were recorded on a Bruker EMX, Continuous Wave X-Band EPR spectrometer (Bruker BioSpin GmbH, Rheinstetten, Germany). Suprasil® ESR tubes with a diameter of 4 mm, length of 250 mm and a wall thickness

• (LUMITRONIX LED-Technik GmbH, Hechingen, Germany) containing 120 LED lamps assembled in an aluminium cylindrical container with a diameter of 8.5 cm. ESR measurements conditions: microwave frequency 9.78 GHz, microwave power 10 mW, receiver gain 5.02 × 104, modulation amplitude 1.00 G, modulation frequency

Synthesis of spiroindolenines through a one-pot multistep process mediated by visible light

• Francesco Gambuti,
• Jacopo Pizzorno,
• Chiara Lambruschini,
• Renata Riva and
• Lisa Moni

Beilstein J. Org. Chem. 2024, 20, 2722–2731, doi:10.3762/bjoc.20.230

• overall yield resulted even better (76% starting from 1 g of N-Ph-THIQ), a slight decrease of the conversion of α-aminoamidine 2d into the spiro[indole-THIQ] 3d was observed. As expected, the use of a larger-diameter reactor caused a low penetration of the irradiation, thus leading to lower efficiency

Deciphering the mechanism of γ-cyclodextrin’s hydrophobic cavity hydration: an integrated experimental and theoretical study

• Stiliyana Pereva,
• Stefan Dobrev,
• Tsveta Sarafska,
• Valya Nikolova,
• Silvia Angelova,
• Tony Spassov and
• Todor Dudev

Beilstein J. Org. Chem. 2024, 20, 2635–2643, doi:10.3762/bjoc.20.221

• the mechanism of its hydration is still a matter of controversial discussion. Too much of a surprise for the scientific community, it has been reported that γ-CD, having the largest cavity (≈9–10 Å in inner diameter) compared to α-CD and β-CD (≈5–6 and ≈7–8 Å in inner diameter, respectively [1][15][16

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

• the assembly across many length scales (Figure 1), and as such characterisation is required across multiple length scales to fully understand these systems. The scale disparity between the diameter of the fibres at the nanoscale, and that of the microscale structure spans 3 to 4 orders of magnitude

• characterise the materials in 0.05, 0.1, and 0.2% agarose, however, due to the significant scattering afforded by agarose dominating the scattering curve, the diameter of the self-assembled fibres in higher concentrations of agarose could not be quantified. At the quantifiable concentrations, SAXS showed the

• diameter of fibres for both Fmoc-DIKVAV and Fmoc-FRGDF to be constant. The consistency of the structures was in contrast to the TEM results, but the in situ nature of the SAXS measurements made them a more reliable measure of the structures present. This showed that there was no correlation between the

Homogeneous continuous flow nitration of O-methylisouronium sulfate and its optimization by kinetic modeling

• Jiapeng Guo,
• Weike Su and
• An Su

Beilstein J. Org. Chem. 2024, 20, 2408–2420, doi:10.3762/bjoc.20.205

• pumped into coiled stainless steel capillary tubes (SS316L, 1/16-inch diameter) that were sufficiently long (1 m). After being preheated to reaction temperature, the material was first initially mixed in a T-mixer (SS316L, 1/16-inch diameter), followed by a homemade static mixer at the outlet of the T

• -mixer to fully mix the material. The reaction coil (SS316L, 1/8-inch diameter) was connected directly to the outlet of the homemade static mixer, nitration took place in the reaction coil. The residence time was precisely controlled by changing the flow rate of the reaction mixture or the length of the

• Jingjin Technology Co., Ltd.) into the second T-mixer. The homemade static mixer consisted of two different mixing units as shown in Figure 2b (total internal volume: 1.3154 mL). The first mixing unit consists of a section of stainless steel coil (SS316L, 1/16-inch diameter, Beijing Xiongchuan Technology

Cage-like microstructures via sequential Ugi reactions in aqueous emulsions

• Rita S. Alqubelat,
• Yaroslava A. Menzorova and
• Maxim A. Mironov

Beilstein J. Org. Chem. 2024, 20, 2078–2083, doi:10.3762/bjoc.20.179

• in dilute aqueous solutions [17]. The use of this method led to the formation of particles with an average diameter in the range of 200–350 nm and with a domain structure. Domains of about 40 nm in size, consisting of CMC, were connected to each other by a soft material based on chitosan. Such

• ) [17]. As before, depending on the CMC concentration, we obtained submicron particles with an average diameter from 200–600 nm, which were visible under an optical microscope in the form of luminous points. Next, Pickering emulsions were obtained by emulsifying toluene in an aqueous suspension of

• removing the solvent, the resulting structure could be easily identified using optical microscopy. They were cage-like microspheres with an average diameter corresponding to the diameter of droplets in the Pickering emulsion (Figure 2). The surface of the droplets was covered with a network of individual

A fiber-optic spectroscopic setup for isomerization quantum yield determination

• Anouk Volker,
• Jorn D. Steen and
• Stefano Crespi

Beilstein J. Org. Chem. 2024, 20, 1684–1692, doi:10.3762/bjoc.20.150

• Avantes AvaLight-DH-S-BAL light source coupled with a 400 µm fiber (Avantes FC-UVIR400-1-BX) to an SMA-to-SM1 fiber adapter (Thorlabs CVH100-COL) containing a plano-convex lens (20.1 mm focal length, Thorlabs LA4647) in a 1 inch diameter lens mount (Thorlabs LMR1S/M). The transmitted light is collected by

• a plano-convex lens (20.1 mm focal length, Thorlabs LA4647) in a 1 inch diameter lens mount (Thorlabs LMR1S/M) contained in an SMA-to-SM1 fiber adapter (Thorlabs CVH100-COL) connected to a 400 µm fiber (Avantes FC-UVIR400-1-BX). The spectrometer we used is an Avantes AvaSpec-ULS2048CL-EVO-RS. The

• light path for the irradiation consists of a fiber-coupled LED (Thorlabs M340F4, M395FP1, M455F3) coupled to a 600 µm fiber (Thorlabs M114L01) to an adjustable fiber collimator (Thorlabs CFCS5-A) mounted on an adapter (Thorlabs AD15F2) in a 1 inch diameter lens mount (Thorlabs LMR1S/M). On the opposite

New triazinephosphonate dopants for Nafion proton exchange membranes (PEM)

• Fátima C. Teixeira,
• António P. S. Teixeira and
• C. M. Rangel

Beilstein J. Org. Chem. 2024, 20, 1623–1634, doi:10.3762/bjoc.20.145

• during 1–5 h, in an ultrasonic bath, to guarantee the complete dissolution of dopants. The resulting solutions were casted on a 5 cm diameter Petri dish and slowly evaporated, until obtaining homogeneous membranes. The resulting membranes were dried in a vacuum oven at 60 °C, and were followed by their

Supramolecular assemblies of amphiphilic donor–acceptor Stenhouse adducts as macroscopic soft scaffolds

• Ka-Lung Hung,
• Leong-Hung Cheung,
• Yikun Ren,
• Ming-Hin Chau,
• Yan-Yi Lam,
• Takashi Kajitani and
• Franco King-Chi Leung

Beilstein J. Org. Chem. 2024, 20, 1590–1603, doi:10.3762/bjoc.20.142

• micelle structures 3–4 nm in diameter (Figure 3b and Figure S8b, Supporting Information File 1). The supramolecular structure of DA11 and the supramolecular transformation were similar to those observed in DA10 [37]. This subtle increase in alkyl linker length in DA11 gave an essentially identical

• screening of DA11 and stabilization as macroscopic soft scaffold. Under an optical microscope, a deep-blue string with a diameter of ≈560 μm was observed in the macroscopic soft scaffold of DA11 (Figure S9, Supporting Information File 1), without any birefringence under crossed polarizers. A macroscopic

• with a diameter of ≈240 μm was observed (Figure 5a and Supporting Information File 2). The macroscopic soft scaffold weakened and shrank in the process. It also partially disassembled upon irradiation for 60 min (Figure 5b), consistent with the behavior of the DA10 macroscopic soft scaffold. With the

Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets

• Guoqing Cheng and
• Naoki Komatsu

Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113

• square nanobrackets, is designed, synthesized and applied to single-walled carbon nanotubes (SWNTs) for their diameter-based separation. The complexation between copper ions and dipyrrin moieties of the nanobracket gives Cu-tethered square nanobrackets, which is confirmed by absorption, Raman and MALDI

• recovered through demetalation of the interlocked ones along with the nanobracket. Raman and absorption spectroscopies of the extracted SWNTs reveals the diameter enrichment of only several kinds of SWNTs in the diameter range from 0.94 to 1.10 nm among ≈20 kinds of SWNTs from 0.76 to 1.20 nm in their

• diameter range. The diameter selectivity is supported by the theoretical calculations with the GFN2-xTB method, indicating that the most preferred SWNT diameter for the square Cu-nanobrackets is 1.04 nm. Keywords: complexation; diameter; extraction; interlock; nanobracket; single-walled carbon nanotubes

Spin and charge interactions between nanographene host and ferrocene

• Akira Suzuki,
• Yuya Miyake,
• Ryoga Shibata and
• Kazuyuki Takai

Beilstein J. Org. Chem. 2024, 20, 1011–1019, doi:10.3762/bjoc.20.89

• three-dimensional disordered network of nanographite domains, each of which is a loose stack of 3–4 nanographene sheets with a mean in-plane size of 2–3 nm. ACFs have huge specific surface areas (about 2000 m2/g [24][25]) due to the presence of nanopores of ca. 1 nm in diameter between the nanographite

Synthesis and characterization of water-soluble C₆₀–peptide conjugates

• Yue Ma,
• Lorenzo Persi and
• Yoko Yamakoshi

Beilstein J. Org. Chem. 2024, 20, 777–786, doi:10.3762/bjoc.20.71

• aggregations in aqueous solution, as observed by dynamic light scattering (DLS), cryoTEM, and concentration-dependent surface tension measurements [40]. Despite the small size (≈10 nm in hydrodynamic diameter), the aggregation of these fullerene moieties was not ideal for biological applications as

• ) revealed an extremely small hydrodynamic diameter (<10 nm) by DLS, 5b (green line) and 5c (purple line) revealed the presence of larger aggregates in water (pH 7.0), with a hydrodynamic diameters larger than 1 µm (Figure 3). In buffer at a higher pH value (e.g., pH 9, TRIS buffer), C60–oligo-Glu (5b

• very small hydrodynamic diameter in a neutral aqueous medium, as shown by DLS analysis. Visible-light-induced 1O2 generation by C60–oligo-Lys (5a) was confirmed by ESR spin trapping. This suggests the high potential of 5a as a basis for a fullerene-derived PS in biological applications. Experimental

Comparison of glycosyl donors: a supramer approach

• Anna V. Orlova,
• Nelly N. Malysheva,
• Maria V. Panova,
• Nikita M. Podvalnyy,
• Michael G. Medvedev and
• Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

• triturated with anhydrous benzene (5 mL), and the extract was filtered through a PTFE microfilter (0.45 μm, 13 mm diameter, Iso-Disk, Supelco). The filtrate was concentrated under reduced pressure and the residue was dried in vacuo to give 2 as a colorless solid (118.8 mg, 73%). [α]D19 −87.4 (c 4.3, CHCl3

Electron-beam-promoted fullerene dimerization in nanotubes: insights from DFT computations

• Laura Abella,
• Gerard Novell-Leruth,
• Josep M. Ricart,
• Josep M. Poblet and
• Antonio Rodríguez-Fortea

Beilstein J. Org. Chem. 2024, 20, 92–100, doi:10.3762/bjoc.20.10

• a hexagon fused with a pentagon) with respect to the nine C atoms (hexagon-pentagon) on the other C60 molecule (see Supporting Information File 1 for details). The armchair-type single-wall carbon nanotube (SWCNT) (10,10) with a length of 22.14 Å and a diameter of 13.65 Å was employed in the

• pseudopotentials [16] while valence electron density was expanded in plane waves with a maximum kinetic energy of 400 eV. The model of SWCNT was 29.61 Å long and with a diameter of 13.65 Å, embedded in a box of 30 × 30 Å of vacuum in the plane perpendicular to the nanotube axis. The gas-phase structures were in a

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

• paths, where consequently the requirements for the application of the Beer–Lambert law are not fulfilled anymore. Considering the inner diameter of the loop reactor of 5 cm, a catalyst loading of 0.11 g L−1 is sufficient to absorb more than 95% of the photons. Photocatalytic hydrogen evolution Long-term

• active materials. Experimental Reactor design The design parameters for the loop photoreactor are based on the optimal design parameters suggested by Blenke et al. [44]. The draft tube diameter is adjusted to achieve maximal mass transfer in the reactor [45][46][47][48]. The design parameters used in

• this work are defined by Equations 6–9: where DR is the inner diameter of the reactor, DD is the inner diameter of the draft tube, LD is the draft tube length, LT is the distance of the draft tube to the reactor top, LB is the distance of the reactor bottom to the draft tube. The reactor is

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• platinum disk (diameter = 1.6 mm) or a glassy carbon disk (3 mm) was used as the working electrode. The reference electrode was separated from the solution containing the substrate by a ceramic frit. Measured potentials were referenced to ferrocene/ferrocenium (Fc/Fc+) redox couple, measured before and

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

• microscopy (AFM) (see Supporting Information File 1, Figure S2). In both images, rod-like DWCNTs were observed, while spaghetti-like agglomerates were hardly observed. The average length (L) and diameter (D) of the DWCNT samples were ≈2.9 μm and ≈2.1 nm, respectively. The L/D of the DWCNTs was 1378, which

• was larger than the value reported in previous research (L/D = 1088) [23]. Based on the transmission electron microscope (TEM) images, the average diameter of DWCNTs was ≈1.8 nm (Supporting Information File 1, Figure S1a). Since the observed DWCNT diameter based on the SEM images is ≈2.1 nm, the

• similar to the previously reported SWCNTs in sodium deoxycholate (SDOC) and sodium taurodeoxycholate (TDOC) aqueous dispersions [23]. The average diameter of DWCNTs in the present study was 2.1 nm, which was almost the same as that of SWCNTs in SDOC and TDOC [23]. Thus, the effect of stiffness of DWCNTs

Facile access to pyridinium-based bent aromatic amphiphiles: nonionic surface modification of nanocarbons in water

• Lorenzo Catti,
• Shinji Aoyama and
• Michito Yoshizawa

Beilstein J. Org. Chem. 2024, 20, 32–40, doi:10.3762/bjoc.20.5

• ; Figure S36 in Supporting Information File 1). The formation of spherical particles with narrow size distribution and an average diameter of ≈2 nm was confirmed by DLS and DOSY NMR measurements (Figure 3e and Figure S27 in Supporting Information File 1). Based on molecular modeling, these data suggested

• )m was roughly estimated to be 0.1 mg mL−1. The DLS measurement of (PA-Im)n·(C60)m displayed an average particle diameter of ≈2 nm, which, in combination with molecular modeling, indicated a noncovalent surface functionalization of a single C60 molecule by five PA-Im amphiphiles (Figure 4d,e

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

• nm, further allowing us to analyze the luminescence dynamics in detail. To determine photoluminescence quantum yields (PLQY), a dedicated integrated sphere with an inner diameter of 120 mm was used in conjunction with the Edinburgh Instruments FLS980 spectrometer. This specialized setup enabled