Biobased carbon dots as photoreductants – an investigation by using triarylsulfonium salts

• Valentina Benazzi,
• Arianna Bini,
• Ilaria Bertuol,
• Mariangela Novello,
• Federica Baldi,
• Matteo Hoch,
• Alvise Perosa and
• Stefano Protti

Beilstein J. Org. Chem. 2025, 21, 1024–1030, doi:10.3762/bjoc.21.84

• predominant band located at 350 nm, CDs synthesized from glucose and bass scales show a significant absorption at around 260 nm and 300 nm, respectively [33][34][35]. A different UV–vis spectrum was obtained for the Blackberries-derived nitrogen-doped material, which showed a main absorption at 330 nm, with a

Synthesis and photoinduced switching properties of C₇-heteroatom containing push–pull norbornadiene derivatives

• Daniel Krappmann and
• Andreas Hirsch

Beilstein J. Org. Chem. 2025, 21, 807–816, doi:10.3762/bjoc.21.64

• result in NBD or in another rearranged species. Conversion of O-NBD1 to O-QC1 using a 275 nm LED. The UV–vis spectrum was recorded in MeCN; b) the respective NMR spectrum was recorded in CDCl3; c) similar UV–vis experiment for N-NBD1 measured in MeCN; d) conversion of N-NBD to an unidentified photoisomer

Unprecedented visible light-initiated topochemical [2 + 2] cycloaddition in a functionalized bimane dye

• Metodej Dvoracek,
• Brendan Twamley,
• Mathias O. Senge and
• Mikhail A. Filatov

Beilstein J. Org. Chem. 2025, 21, 500–509, doi:10.3762/bjoc.21.37

• ¹H NMR spectra remained unchanged compared to the neat compounds (Figures S1, S3, and S5, Supporting Information File 1), confirming that the reaction occurs selectively in the solid state. Cl2B was also irradiated in DCM with the same 405 nm LEDs, in a quartz fluorescence cuvette. A UV–vis spectrum

• its photophysical properties. While a pure sample of the dimer has not yet been isolated, a UV–vis spectrum of Cl2B after 1.75 hours of irradiation in DCM was recorded. The peak corresponding to the remaining monomer was observed, along with a new peak blueshifted by 47 nm compared to the parent

• displacement parameter restraints. View of the packing of the unit cells of a) Me2B viewed normal to the c-axis and b) Me4B viewed normal to (110). Only the majority occupied moiety of the N–N bridge is shown in Me4B. UV–vis spectrum of Cl2B after irradiation in DCM. Proposed mechanism for the topochemical [2

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

• ]+ (calculated 446.1962). The UV–vis spectrum of 1 (Figure S3, Supporting Information File 1) revealed a prominent absorption peak (λmax) at 434 nm in the visible region reflected by being yellow-colored and suggesting the presence of an extended conjugated π-system in its structure. The 1H NMR and 1H–1H COSY

Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• the optical properties of 18 in CHCl3 (c = 100 μM) by measuring its UV–vis absorption spectrum as well as its excitation and emission spectra. The UV–vis spectrum of 18 showed two absorption peaks at 334 nm and around 375 nm (gray solid line). When excited at 375 nm, the emission spectra of 18

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• the UV–vis spectrum revealed a red shift, indicating the presence of diprotonated H4TPP2+ macrocycle (Figure 21a). Fc addition into an air-saturated DCE solution containing 18 (H2TPP) and HTB led to oxidation of Fc to Fc+ and initiated the ORR process (Figure 20b). The rate of ferrocene oxidation (Fc

Synthesis and reactivity of the di(9-anthryl)methyl radical

• Tomohiko Nishiuchi,
• Kazuma Takahashi,
• Yuta Makihara and
• Takashi Kubo

Beilstein J. Org. Chem. 2024, 20, 2254–2260, doi:10.3762/bjoc.20.193

• spectrum shape (Supporting Information File 1, Figure S10). On the other hand, the UV–vis spectrum of the DAntM cation, generated from 3 in TFA solution, showed an intense absorption band at 890 nm, which is the opposite trend compared to the DAntM radical. Conclusion The synthesis and characterization of

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

• spectra of thus synthesized truxenes (12, 14, 15, 16, 17, and 18) were analyzed in CHCl3 (Figure 2). The UV–vis spectrum of mono-acetyltruxene 12 displayed a broad band centered at 335.21 nm, an intense peak near 309.75 nm having a shoulder at 297.70 nm, and a less intense, broader band around 280.29 nm

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

• this way, when a UV–vis spectrum is recorded, the shutter of the D2-tungsten lamp is open and the excitation LED is switched off for the entirety of the measurement (average of 500 spectra acquired for 1.0 ms). When the measurement is finished, the script closes the shutter and the LED is switched on

Competing electrophilic substitution and oxidative polymerization of arylamines with selenium dioxide

• Vishnu Selladurai and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2024, 20, 1221–1235, doi:10.3762/bjoc.20.105

• polymer 1. The polymer was isolated from the reaction after 3 h, and the supernatant was analyzed for other soluble products. The UV–vis spectrum of polymer 1 dispersed in methanol showed two major peaks at ≈271 and ≈561 nm (Figure S1, Supporting Information File 1), corresponding to the π→π* and

Introduction of peripheral nitrogen atoms to cyclo-meta-phenylenes

• Koki Ikemoto and
• Hiroyuki Isobe

Beilstein J. Org. Chem. 2024, 20, 1207–1212, doi:10.3762/bjoc.20.103

• dopants. Photophysical properties of 3a and 3b. (a) UV–vis spectrum of 3a in CHCl3. (b) UV–vis spectrum of 3b in CHCl3. For reference, the spectra of [6]CMP and [8]CMP from the literature are also shown in gray [15]. Crystal structures of 3a and 3b. (a) Molecular structures. Biaryl dihedral angles (ω) are

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

• /CH2Cl2 5:1 as solvent mixture. Although several other fractions containing C60 derivatives were obtained, their structures are still under investigation because of the difficulty in isolating and purifying those fractions. To clarify the addition site of 3, we measured the ultraviolet–visible (UV–vis

• ) spectrum. Fullerene derivatives are well-known to show characteristic absorption spectra depending on the addition pattern. As shown in Figure 2, the spectrum of 3 exhibited an absorption maximum at 515 nm, which is similar to those of the e′ and e′′ isomers of C60[C(C6H4OMe)2]2 and C60[C(C6H4OMe)2][NCOOEt

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

• found to be in a good agreement with the experimentally determined UV–vis spectrum. Conclusion A small fluorophore molecule, DMB-TT-TPA (8), containing dimesitylboron as an acceptor and triphenylamine as a donor linked through a thieno[3,2-b]thiophene core having a 4-MeOPh group, was designed as a D–π–A

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• stability in aqueous medium. Thus, the electronic absorption spectra of hdz-CH3 and hdz-NO2 were recorded in a 10% DMSO/buffer solution (pH 7.4) immediately after preparation and at regular time intervals. The UV–vis spectrum of hdz-CH3 between 250 and 450 nm (Figure 6A) shows two multicomponent absorptions

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

• , featuring no significant vibronic structure, and a considerably large Stokes shift of 140 nm. The UV–vis absorption and PL spectra of spin-coated films were similar to those of dilute solutions. Based on the onset energy of this UV–vis spectrum, the optical band gap (Egopt) was estimated to be 2.04 eV

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

CO₂ complexation with cyclodextrins

• Cecilie Høgfeldt Jessen,
• Jesper Bendix,
• Theis Brock Nannestad,
• Heloisa Bordallo,
• Martin Jæger Pedersen,
• Christian Marcus Pedersen and
• Mikael Bols

Beilstein J. Org. Chem. 2023, 19, 1021–1027, doi:10.3762/bjoc.19.78

• using a pressure cell and a UV–vis competition assay with an azo-dye (4-((4-hydroxyphenyl)azo)-1-naphthalenesulfonic acid (7) Figure 4) [15] as an indicator. The UV–vis spectrum of 7 changes on binding to cyclodextrins and we can thereby indirectly monitor the binding of CO2 to the CD by observing the

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

• success in the increase of tetracene solubility, we struggled to evaluate the supramolecular interaction. Unfortunately, it seems that the complexation does not change the position of the chemical shifts on the NMR spectra and the shape or intensity of the UV–vis spectrum. The decrease in the guest's

Study on the interactions between melamine-cored Schiff bases with cucurbit[n]urils of different sizes and its application in detecting silver ions

• Jun-Xian Gou,
• Yang Luo,
• Xi-Nan Yang,
• Wei Zhang,
• Ji-Hong Lu,
• Zhu Tao and
• Xin Xiao

Beilstein J. Org. Chem. 2021, 17, 2950–2958, doi:10.3762/bjoc.17.204

• with strong host–guest interaction. In addition, we also used the UV–vis spectrum to verify the above inference and to further investigate their molar ratio in detail. Q[7] has a larger cavity than TMeQ[6], giving it the ability to bind TBT. Therefore, the absorbance of TBT gradually decreases and

• addition, the UV–vis spectrum in Figure 4a shows that the absorbance of TBT keeps on the decrease (ΔA = 0.623) without red shift or blue shift in the presence of Q[8]. Both of the above phenomena show that Q[8] interacted with the “arm” of TBT and produced precipitation due to aggregation, which is also

Chemical syntheses and salient features of azulene-containing homo- and copolymers

• Vijayendra S. Shetti

Beilstein J. Org. Chem. 2021, 17, 2164–2185, doi:10.3762/bjoc.17.139

• of polymerization of ≈7) leaving speculation about a higher degree of polymerization for the THF-insoluble component of PAZ-Br2. The UV–vis spectrum of the chloroform-soluble fraction of PAZ-Br2 displayed absorption bands in the 190–330 nm region like the azulene monomer, and a long tail with a broad

Constrained thermoresponsive polymers – new insights into fundamentals and applications

• Patricia Flemming,
• Alexander S. Münch,
• Andreas Fery and
• Petra Uhlmann

Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138

Synthetic reactions driven by electron-donor–acceptor (EDA) complexes

• Zhonglie Yang,
• Yutong Liu,
• Kun Cao,
• Xiaobin Zhang,
• Hezhong Jiang and
• Jiahong Li

Beilstein J. Org. Chem. 2021, 17, 771–799, doi:10.3762/bjoc.17.67

• phenomena based on the electron-donor–acceptor (EDA) complex [1][2][3]. Significantly, a broad absorption peak unrelated to the structure, called charge-transfer band, is typically located in the visible region of the UV–vis spectrum [4], which manifests the color variability of the mixed solution of the

The fluorescence of a mercury probe based on osthol

• Guangyan Luo,
• Zhishu Zeng,
• Lin Zhang,
• Zhu Tao and
• Qianjun Zhang

Beilstein J. Org. Chem. 2021, 17, 22–27, doi:10.3762/bjoc.17.3

• to a higher field. Because Hh is located in the central area of the shield and Hi is at the edge of the shield, the Δδ value of Hh is relatively large, and finally both moved to δ 1.35. Based on the 1H NMR and mass spectrometry data, combined with the analysis of the UV–vis spectrum, the interaction

A heterobimetallic tetrahedron from a linear platinum(II)-bis(acetylide) metalloligand

• Matthias Hardy,
• Marianne Engeser and
• Arne Lützen

Beilstein J. Org. Chem. 2020, 16, 2701–2708, doi:10.3762/bjoc.16.220

• , correlation of the proton. Low- and high-resolution electrospray ionization mass spectrometry (ESIMS) spectra were recorded on a Bruker Daltonic LTQ Orbitrap XL. The UV–vis spectrum was recorded on a Specord 200 spectrometer (Analytik Jena AG) at ambient temperature. 4-Ethynylaniline (1) [50], trans-[Pt(PBu3

• spectrum of heterobimetallic complex 4. The top inset shows the experimentally observed and the calculated isotopic pattern for the signal of [4 − 7 OTf]7+. The lower inset shows observed cage fragments a–d. UV–vis spectrum of heterobimetallic complex 4 (1150 µM in acetonitrile at 295 K, 0.01 mm cuvette

Optical detection of di- and triphosphate anions with mixed monolayer-protected gold nanoparticles containing zinc(II)–dipicolylamine complexes

• Lena Reinke,
• Julia Bartl,
• Marcus Koch and
• Stefan Kubik

Beilstein J. Org. Chem. 2020, 16, 2687–2700, doi:10.3762/bjoc.16.219

• signals of the immobilized ligand molecules but no sharp signals, showing that the nanoparticles were not contaminated with unbound ligands or residual citrate. According to transmission electron microscopy (TEM), NPrac-1 had an average diameter of 9.1 ± 2.4 nm and a maximum of the SPR band in the UV–vis

• spectrum at 528 nm (Figure S1 in Supporting Information File 1). Further structural information was obtained by releasing the ligand molecules from the surface of NPrac-1 with iodine, adding a known amount of 2,4,6-trimethoxy-1,3,5-triazine to the solution as an internal standard, and recording an 1H NMR