Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

• Eugeny Ivakhnenko,
• Vasily Malay,
• Pavel Knyazev,
• Nikita Merezhko,
• Nadezhda Makarova,
• Oleg Demidov,
• Gennady Borodkin,
• Andrey Starikov and
• Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

• 15N NMR spectroscopy (NMR spectra of compounds 4a–h, 5a–c, 6a,b, and 10c are given in Figures S13–S43, Supporting Information File 1), mass spectrometry (Figures S44–S56, Supporting Information File 1), IR and UV–vis spectroscopy, as well as elemental analysis. The NMR spectra were recorded on the

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

• using a high-pressure mercury lamp equipped with a sharp cut filter (λ > 380 nm), which resulted in a smooth conversion into the PBI product 6a within 20 min. Interestingly, the sulfoxide derivative exhibited enhanced kinetics, as confirmed by UV–vis spectroscopy and NMR experiments. The latter was also

Unveiling the regioselectivity of rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition reactions for open-cage C₇₀ production

• Cristina Castanyer,
• Anna Pla-Quintana,
• Anna Roglans,
• Albert Artigas and
• Miquel Solà

Beilstein J. Org. Chem. 2024, 20, 272–279, doi:10.3762/bjoc.20.28

• we analyzed by UV–vis spectroscopy. This peak was assigned as a bis(fulleroid) compound by comparing the spectra with the UV–vis absorption pattern exhibited by previously characterized C70 bis(fulleroids) reported by Murata et al. [43][48]. In addition, a minor peak at a retention time of 20 minutes

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• between P1 and C15 is slightly longer (1.824(2) Å in 2a; 1.828(3) in 2f) when compared to the P–CH2 distance of a tetra-n-butylphosphonium cation [45]. UV–vis spectroscopy All phosphonium phenolate compounds exhibit a bright yellow color in solution (see inset in Figure 3). Investigating the absorption

• study was performed by monitoring the appearance of the zwitterion absorption by means of UV–vis spectroscopy in chloroform or in methanol as the solvent. The concentration of the respective Michael acceptor was varied ([Michael acceptor] = 2.5 mmol/L to 10 mmol/L) and was at least ten-fold higher than

Tying a knot between crown ethers and porphyrins

• Maksym Matviyishyn and
• Bartosz Szyszko

Beilstein J. Org. Chem. 2023, 19, 1630–1650, doi:10.3762/bjoc.19.120

• the aryl group at the meso-position of the dipyrrin moiety. Compound 40 was tested for sensing metal ions, and while no significant changes were observed with most cations, the addition of Cu(II) resulted in a colour change. UV–vis spectroscopy and mass spectrometry confirmed the 1:1 copper(II

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

A fluorescent probe for detection of Hg²⁺ ions constructed by tetramethyl cucurbit[6]uril and 1,2-bis(4-pyridyl)ethene

• Xiaoqian Chen,
• Naqin Yang,
• Yue Ma,
• Xinan Yang and
• Peihua Ma

Beilstein J. Org. Chem. 2023, 19, 864–872, doi:10.3762/bjoc.19.63

• detection of heavy metal ions. Results and Discussion The interactions of G with TMeQ[6] UV–vis spectroscopy analysis The binding interaction between G and TMeQ[6] in aqueous solution was studied using UV–vis absorption spectroscopy. Figure 2a shows that the absorbance of G decreases with the addition of

• , which is an exothermic reaction (enthalpy-driven). The results show that the binding ability of G and TMeQ[6] is strong, and the ratio is 1:1. The results are consistent with those obtained by UV–vis spectroscopy and fluorescence spectroscopy. Single-crystal X-ray diffraction analysis The crystal

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene

• Semyon V. Tsybulin,
• Ekaterina A. Filatova,
• Alexander F. Pozharskii,
• Valery A. Ozeryanskii and
• Anna V. Gulevskaya

Beilstein J. Org. Chem. 2023, 19, 674–686, doi:10.3762/bjoc.19.49

• -conjugation of 1,8-bis(dimethylamino)naphthalene (DMAN) fragments through a butadiyne linker and a donor–acceptor aryl–C≡C–DMAN conjugation path. The conjugation path can be “switched” simply by protonation of DMAN fragments. X-ray diffraction, UV–vis spectroscopy and cyclic voltammetry are applied to analyze

• us to undertake the current study. X-ray crystallography, UV–vis spectroscopy and cyclic voltammetry were applied to analyze the extent of π-electron conjugation and the efficiency of the particular donor–acceptor conjugation path in chromophores 5. Results and Discussion Synthesis The target

• UV–vis spectroscopy data. Butadiynes 5 having electron-withdrawing CN and NO2 substituents in the aryl moieties demonstrated the longest wavelength absorption maxima in the series. The optical band gaps (Egopt), estimated from the onset point of the absorption spectra of 5, ranged within 2.39 eV (for

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• )-catalyzed click reaction between 5,10,15,20-tetrakis(3,5-dipropargyloxyphenyl)-Zn-porphyrin 173 and the azide 124 in the presence of CuSO4 and sodium ascorbate in THF/H2O (Scheme 38). UV–vis spectroscopy showed that the porphyrin 174 was readily soluble in water, and no porphyrin–porphyrin stacking

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

• or TOF. The drying and nebulizer gas was nitrogen. High-resolution mass spectra were measured with an Agilent Technologies 6530 Accurate-Mass Q-TOF LC/MS spectrometer. Samples were ionized by electrospray technique (ESI) and detected by quadrupole or TOF. UV–vis spectroscopy spectra were measured

Synthesis of α-(perfluoroalkylsulfonyl)propiophenones: a new set of reagents for the light-mediated perfluoroalkylation of aromatics

• Durbis J. Castillo-Pazos,
• Juan D. Lasso and
• Chao-Jun Li

Beilstein J. Org. Chem. 2022, 18, 788–795, doi:10.3762/bjoc.18.79

• this work, especially Robin Stein and Tara Sprules on the NMR data, Hatem Titi on SCXRD interpretation, Nadim Saadé and Alexander Wahba on HRMS, and Petr Fiurasek and Ehsan Hamzehpoor on UV–vis spectroscopy. Funding The authors acknowledge the Canada Research Chair (Tier I) foundation, the E.B. Eddy

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

• hydrogen of TMeQ[6] on its outer surface. In addition, when using UV–vis spectroscopy (Figure S5 and Supporting Information File 1, Figure S6) to investigate their interaction, it’s found that the presence of TMeQ[6] does not affect the absorbance of TBT, indicating that TMeQ[6] prefers to interact with

Host–guest interaction and properties of cucurbit[8]uril with chloramphenicol

• Lin Zhang,
• Jun Zheng,
• Guangyan Luo,
• Xiaoyue Li,
• Yunqian Zhang,
• Zhu Tao and
• Qianjun Zhang

Beilstein J. Org. Chem. 2021, 17, 2832–2839, doi:10.3762/bjoc.17.194

• ] and CPE was investigated using UV–vis spectroscopy utilizing the molar ratio and Job's method under neutral conditions (Figure 3). Figure 3A shows that CPE has a strong absorption peak at λ = 278 nm and the absorption intensity gradually decreases after the continuous addition of Q[8]. When n(Q[8])/n

Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring

• Cansu Esen and
• Baris Kumru

Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92

• , and at last the intensified peak at 1419 cm−1 indicates a C–N stretching of the thiazole ring. Proceeding the examination by UV–vis spectroscopy, overlaid absorption spectra of the samples revealed the photophysical differences as expected, since HG does not consist of photoactive g-CN particles in

• profiles of RhB swollen hydrogels. HG, HGCM, and HGCM-vTA have been immersed in RhB solution for 24 hours, then washed with distilled water every 24 hours, and all collected samples were investigated by UV–vis spectroscopy until reaching the minimum dye absorbance (Figure 3c,d, Supporting Information File

• , respectively, and left overnight. Released contents of each cation were analyzed via ICP-OES. Characterization: Fourier transform infrared (FTIR) spectra were acquired on a Nicolet iS 5 FT-IR spectrometer. Solid-state ultraviolet−visible (UV−vis) spectroscopy for grinded samples was performed via a Cary 500

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

• between radicals was carried out, affording thioether derivative 132 (Scheme 46). It has been proved by UV–vis spectroscopy and TDDFT calculations that the EDA complex was formed between an electron-rich mercaptan anion and electron-deficient aryl halides. Most importantly, this approach can be

• haloalkanes, the highest yield was given. Since a marked yellow color appeared immediately upon mixing substrates, the existence of an EDA complex could be confirmed by UV–vis spectroscopy. Conclusion In this review, reactions and mechanisms of EDA complexes were discussed from the aspects of cyclization

Mesoionic tetrazolium-5-aminides: Synthesis, molecular and crystal structures, UV–vis spectra, and DFT calculations

• Vladislav A. Budevich,
• Sergei V. Voitekhovich,
• Alexander V. Zuraev,
• Vadim E. Matulis,
• Vitaly E. Matulis,
• Alexander S. Lyakhov,
• Ludmila S. Ivashkevich and
• Oleg A. Ivashkevich

Beilstein J. Org. Chem. 2021, 17, 385–395, doi:10.3762/bjoc.17.34

• -(methylsulfonyl)-1-phenyl-1H-tetrazole with substitution of bromine and methylsulfonyl groups giving the corresponding tetrazolium salts or conjugate aminides. The obtained mesoionic tetrazoles have been characterized by elemental analysis, FTIR, NMR, and UV–vis spectroscopy, TGA/DSC analysis and for 1,3-di-tert

• and 5-(methylsulfonyl)-1-phenyl-1H-tetrazole and substitute bromine and methylsulfonyl groups giving tetrazolium salts or conjugate aminides. The obtained mesoionic tetrazoles have been characterized by elemental analysis, FTIR, NMR and UV–vis spectroscopy, TGA/DSC analysis, and for 1,3-di-tert

Annulation of a 1,3-dithiole ring to a sterically hindered o-quinone core. Novel ditopic redox-active ligands

• Sergey V. Norkov,
• Anton V. Cherkasov,
• Andrey S. Shavyrin,
• Maxim V. Arsenyev,
• Viacheslav A. Kuropatov and
• Vladimir K. Cherkasov

Beilstein J. Org. Chem. 2021, 17, 273–282, doi:10.3762/bjoc.17.26

• found to be a stronger oxidant than 36Q [16]. A very similar redox behavior and shifts of reduction potential values were observed for p-quinone derivatives with attached 1,3-dithiole rings [27][49]. UV–vis spectroscopy Sterically hindered o-quinones are deep-colored compounds. Any changes in their

Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies

• Alexander Zika and
• Franziska Gröhn

Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17

• particles, and information on the molecular structure was gained by UV–vis spectroscopy. Isothermal titration calorimetry (ITC) provided information on the thermodynamics and interaction forces in the supramolecular assembly formation. Keywords: electrostatic self-assembly; hydroxyflavylium

• followed with UV–vis spectroscopy to monitor the differences between the states. As can be seen in Figure 1, the different forms of Flavy vary in the light absorption. While the forms A and AH+ show an absorption at λ = 500 and λ = 550 nm, respectively, due to their expanded electronic system, the

• . To follow the changes of the molecules and the nano-assemblies, the samples were monitored by UV–vis spectroscopy, as shown in Figure 3. The non-irradiated sample shows a broad band at λ = 550 nm, which corresponds to Flavy as evident in comparison with Figure 1. The difference compared to the pure

Construction of pillar[4]arene[1]quinone–1,10-dibromodecane pseudorotaxanes in solution and in the solid state

• Xinru Sheng,
• Errui Li and
• Feihe Huang

Beilstein J. Org. Chem. 2020, 16, 2954–2959, doi:10.3762/bjoc.16.245

• of G on the optical properties of H, so an UV–vis spectroscopy experiment was carried out. We investigated the changes in the UV–vis absorption of the complex at different guest concentrations corresponding to 0.5 and 1 equiv. As shown in Figure 4, the concentration of G did not affect the absorption

Incorporation of a metal-mediated base pair into an ATP aptamer – using silver(I) ions to modulate aptamer function

• Marius H. Heddinga and
• Jens Müller

Beilstein J. Org. Chem. 2020, 16, 2870–2879, doi:10.3762/bjoc.16.236

• washing with buffer. The elution was quantified by UV–vis spectroscopy. In the absence of Ag(I), the aptamer derivatives bearing imidazole residues show a lower affinity to ATP than the unmodified aptamer (Figure 9). While only 17% of the DNA is eluted in the five washing fractions of 1af, the amount of

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

• diastereomers. The new complexes were characterized by NMR and UV–vis spectroscopy and ESI mass spectrometry. Using GFN2-xTB we generated energy-minimized models of the diastereomers of this cage that further corroborated the results from analytical findings. Keywords: cage compounds; heterobimetallic

• UV–vis spectroscopy. The spectrum of tetrahedron 4 in acetonitrile solution revealed multiple absorption maxima. The most prominent maxima are located at 200 and 294 nm with a shoulder at 360 nm, probably corresponding to π–π* transitions from the aromatic systems and the triple bonds. Finally, a

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

• sensing, even when simultaneously present at concentrations significantly higher than the actual analyte. The effects of the phosphate salts on the solutions of all four nanoparticles were then followed in a more precise fashion by using UV–vis spectroscopy. To this end, the solutions of the four

Synthesis of 4-substituted azopyridine-functionalized Ni(II)-porphyrins as molecular spin switches

• Jannis Ludwig,
• Tobias Moje,
• Fynn Röhricht and
• Rainer Herges

Beilstein J. Org. Chem. 2020, 16, 2589–2597, doi:10.3762/bjoc.16.210

• and 1j because of paramagnetic line broadening and overlapping signals. To circumvent these problems, UV–vis spectroscopy was performed at very low concentrations (Table 1). The porphyrin Soret bands are different for the diamagnetic (λmax ≈ 406 nm) and the paramagnetic species (λmax ≈ 423 nm). The

Water-soluble host–guest complexes between fullerenes and a sugar-functionalized tribenzotriquinacene assembling to microspheres

• Si-Yuan Liu,
• Xin-Rui Wang,
• Man-Ping Li,
• Wen-Rong Xu and
• Dietmar Kuck

Beilstein J. Org. Chem. 2020, 16, 2551–2561, doi:10.3762/bjoc.16.207

• affinity of C70-fullerene may be attributed to its larger size and surface area as compared to C60-fullerene [50]. The complexation between TBTQ-(OG)6 and fullerenes was also examined by UV–vis spectroscopy in both toluene/DMSO 1:1 (v/v) and water. Figure 3a shows the UV–vis spectra of TBTQ-(OG)6, C60 and

The B & B approach: Ball-milling conjugation of dextran with phenylboronic acid (PBA)-functionalized BODIPY

• Patrizia Andreozzi,
• Lorenza Tamberi,
• Elisamaria Tasca,
• Gina Elena Giacomazzo,
• Marta Martinez,
• Mirko Severi,
• Marco Marradi,
• Stefano Cicchi,
• Sergio Moya,
• Giacomo Biagiotti and
• Barbara Richichi

Beilstein J. Org. Chem. 2020, 16, 2272–2281, doi:10.3762/bjoc.16.188

• by UV–vis spectroscopy (λmax = 508–511 nm). The DMSO/ethanol mixtures and ethanol solutions were dried under vacuum, the recovered dye was solubilized in DMSO, and the UV–vis spectra were recorded. The amount of recovered PBA-BODIPY (1) was estimated (Figure 2A), using the molar extinction

• by means of UV–vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and transmission electron microscopy (TEM) analysis (see Supporting Information File 1). Concerning the chemical structure of the conjugate, the data reported in the literature were