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

Naphthalene diimide bis-guanidinio-carbonyl-pyrrole as a pH-switchable threading DNA intercalator

• Poulami Jana,
• Filip Šupljika,
• Carsten Schmuck and
• Ivo Piantanida

Beilstein J. Org. Chem. 2020, 16, 2201–2211, doi:10.3762/bjoc.16.185

• charges, while at pH 5 both GCP moieties are also protonated, yielding 4 with four positive charges [18]. The concentration dependence of 4 according to its UV–vis spectrum at both, pH 5 and 7, was linear up to 2 × 10−5 M (Supporting Information File 1), supporting the presence of single, non-aggregated 4

• molecules in water. The absorption maxima and corresponding molar extinction coefficients (ε) are given in Table S1 (Supporting Information File 1). Heating of the aqueous solution of 4 up to 90 °C did not yield any significant changes in its UV–vis spectrum, suggesting that the chromophores are not

• involved in intra- or intermolecular stacking interactions. The excellent reproducibility of the UV–vis spectrum upon cooling back to room temperature (Figure S2, Supporting Information File 1) verified the chemical stability of the compound. The aqueous solution of the studied compound 4 was non

Synthesis of 6,13-difluoropentacene

• Matthias W. Tripp and
• Ulrich Koert

Beilstein J. Org. Chem. 2020, 16, 2136–2140, doi:10.3762/bjoc.16.181

• -difluoroanthracene. This strategy could be applicable for the synthesis of differently substituted 6,13-difluoropentacenes as well. Structures of pentacene and fluorinated pentacenes. UV–vis spectrum of F2PEN 5 in CH2Cl2. Retrosynthetic analysis of F2PEN 5. Synthesis of F2PEN 5. Decomposition of diol 13 in solution

One-pot synthesis of dicyclopenta-fused peropyrene via a fourfold alkyne annulation

• Ji Ma,
• Yubin Fu,
• Junzhi Liu and
• Xinliang Feng

Beilstein J. Org. Chem. 2020, 16, 791–797, doi:10.3762/bjoc.16.72

• -membered ring B. The large difference between the LUMO and HOMO leads to an intramolecular charge transfer, resulting in broad absorption bands in the UV–vis spectrum (Figure 3a) [36]. In addition, the LUMO energy of 1 (−2.98 eV) is significantly lower than that of 6 (−2.38 eV), which is responsible for

Synthesis of C₇₀-fragment buckybowls bearing alkoxy substituents

• Yumi Yakiyama,
• Shota Hishikawa and
• Hidehiro Sakurai

Beilstein J. Org. Chem. 2020, 16, 681–690, doi:10.3762/bjoc.16.66

• dialkoxides (Figure 6b). In contrast, 5c exhibited different features in both UV–vis and emission spectra from the other two. In the UV–vis spectrum of 5c, the splitted sharp absorptions at 266 and 287 nm and a broad band at 320 nm together with a relatively strong broad band at 409 nm are visible. The

Synthesis and characterization of bis(4-amino-2-bromo-6-methoxy)azobenzene derivatives

• David Martínez-López,
• Amirhossein Babalhavaeji,
• Diego Sampedro and
• G. Andrew Woolley

Beilstein J. Org. Chem. 2019, 15, 3000–3008, doi:10.3762/bjoc.15.296

• be insoluble in water. We therefore dissolved 4 in DCM to obtain the UV–vis spectrum of the neutral form. Addition of TFA to this solution produced the corresponding azonium ion, and the spectra of the neutral and azonium forms of 4 are shown as solid lines in Figure 2. Observed absorption maxima

• neutral pH, creating a doubly charged species. As anticipated, compound 5 was found to be much more water-soluble than 4. The UV–vis spectrum of 5 at a neutral pH value is shown in Figure 4. Irradiation with blue light at 440 nm produced the PSS (dotted line). Thermal reversion from the cis isomer was

• monitored by UV–vis spectroscopy, recording a UV–vis spectrum every 3 minutes, and a half-life of 12.6 minutes was obtained. The formation of the azonium ion of 5 in aqueous solution was explored thereafter. Addition of hydrochloric acid to a neutral solution of 5 was carried out. Spectra at different pH

Nanangenines: drimane sesquiterpenoids as the dominant metabolite cohort of a novel Australian fungus, Aspergillus nanangensis

• Heather J. Lacey,
• Cameron L. M. Gilchrist,
• Andrew Crombie,
• John A. Kalaitzis,
• Daniel Vuong,
• Peter J. Rutledge,
• Peter Turner,
• John I. Pitt,
• Ernest Lacey,
• Yit-Heng Chooi and
• Andrew M. Piggott

Beilstein J. Org. Chem. 2019, 15, 2631–2643, doi:10.3762/bjoc.15.256

• -resolution positive electrospray ionisation mass spectrometry (HRESI(+)MS) analysis of nanangenine A (1) revealed an adduct ion ([M + Na]+ m/z 305.1363) indicative of a molecular formula C15H22O5 requiring five double bond equivalents (DBE). No distinguishing absorption maxima were observed in the UV–vis

• spectrum, while absorptions at 3354 and 1738 cm−1 in the IR spectrum were indicative of hydroxy and carbonyl groups, respectively. The 13C NMR data for 1 (Table 1) indicated the presence of one carbonyl carbon (δC 179.3, C-11) and two olefinic carbons (δC 128.2, C-7 and δC 131.1, C-8), accounting for two

A new approach to silicon rhodamines by Suzuki–Miyaura coupling – scope and limitations

• Thines Kanagasundaram,
• Antje Timmermann,
• Carsten S. Kramer and
• Klaus Kopka

Beilstein J. Org. Chem. 2019, 15, 2569–2576, doi:10.3762/bjoc.15.250

• of Stefan Hell, MPI for Medical Research Heidelberg) for measurement of the UV–vis spectrum of 30c.

Experimental and computational electrochemistry of quinazolinespirohexadienone molecular switches – differential electrochromic vs photochromic behavior

• Eric W. Webb,
• Jonathan P. Moerdyk,
• Kyndra B. Sluiter,
• Benjamin J. Pollock,
• Amy L. Speelman,
• Eugene J. Lynch,
• William F. Polik and
• Jason G. Gillmore

Beilstein J. Org. Chem. 2019, 15, 2473–2485, doi:10.3762/bjoc.15.240

• assignment. UV–vis spectra taken of eLW solutions generated by bulk electrolysis in acetonitrile and acetonitrile-d3 were compared against photoirradiated (pLW) solutions. No difference was observed in the UV–vis spectrum of the LW isomer prepared from either photolysis or electrolysis of solutions of 1b (as

• photolyzed solution (4a) versus 529 nm for the electrolyzed (5a). Similarly, for 4b and 5b, the photolyzed λmax in acetonitrile was 558 nm versus 549 nm for the electrogenerated and was 564 nm versus the electrogenerated 550 nm in acetonitrile-d3. The differences in the UV–vis spectrum of about 10 nm between

• would be expected to be noticeable but not large. Observation of no difference in the UV–vis spectrum of the LW isomer prepared from either photolysis or electrolysis of solutions of 1b (able to only form one LW isomer, 2b) supports the formation of two different LW isomers for 3a,b rather than

Azologization and repurposing of a hetero-stilbene-based kinase inhibitor: towards the design of photoswitchable sirtuin inhibitors

• Christoph W. Grathwol,
• Nathalie Wössner,
• Sören Swyter,
• Adam C. Smith,
• Enrico Tapavicza,
• Robert K. Hofstetter,
• Anja Bodtke,
• Manfred Jung and
• Andreas Link

Beilstein J. Org. Chem. 2019, 15, 2170–2183, doi:10.3762/bjoc.15.214

• absorption maximum, the UV–vis spectrum of 2b developed a more complex structure with further illumination. The initial spectrum did not restore, neither thermally by standing in the dark nor photochemically when exposed to daylight. Regarding 2f, 254 nm radiation was obligatory to obtain changes in the UV

• hit compound GW435821X (2a). (Left) UV–vis spectrum of 2b 50 µM in 5% DMSO (v/v) in assay buffer after varying durations of irradiation with 254 nm and 365 nm, respectively. (Right) UV–vis spectrum of 2f 50 µM in 5% DMSO (v/v) in assay buffer after varying durations of UV radiation. (Left) LC

• –HRMS analysis of 2f after varying durations of irradiation with 254 nm. Calculated and experimental absorption spectra of compounds (E)-2b-B (A), (Z)-2b-A (B), and products 8a (C) and 8b (D). Oscillator strengths (green sticks) correspond to the ADC(2)/COSMO calculation. (Left) UV–vis spectrum of 11

A golden opportunity: benzofuranone modifications of aurones and their influence on optical properties, toxicity, and potential as dyes

• Joza Schmitt and
• Scott T. Handy

Beilstein J. Org. Chem. 2019, 15, 1781–1785, doi:10.3762/bjoc.15.171

• . In this study, the influence of substitution in the benzofuranone ring on the UV–vis spectrum is explored, as well as an initial screening of their toxicity and a qualitative preliminary study of their potential to act as fabric dyes. Keywords: aurone; dyeing; dyes; substitution effect; toxicity; UV

• –vis spectrum; Introduction Aurones are a fascinating minor sub-family of the flavonoid natural products [1][2]. While they feature the same C15 composition as other flavonoids, the skeleton is quite different, featuring a benzofuranone connected to an aromatic ring via an exocyclic alkene. This

Synthesis, enantioseparation and photophysical properties of planar-chiral pillar[5]arene derivatives bearing fluorophore fragments

• Guojuan Li,
• Chunying Fan,
• Guo Cheng,
• Wanhua Wu and
• Cheng Yang

Beilstein J. Org. Chem. 2019, 15, 1601–1611, doi:10.3762/bjoc.15.164

• -resolution mass spectrometry (HRMS, Supporting Information File 1, Figures S19–S21). Photophysical properties The photophysical properties were investigted by UV–vis absorption and fluorescence spectroscopy, as well as through fluorescence decay measurements. As shown in Figure 1a, the UV–vis spectrum of P5A

Azologization of serotonin 5-HT₃ receptor antagonists

• Karin Rustler,
• Galyna Maleeva,
• Piotr Bregestovski and
• Burkhard König

Beilstein J. Org. Chem. 2019, 15, 780–788, doi:10.3762/bjoc.15.74

• be followed by a decrease of the trans-absorption maximum at around 350–400 nm and an increase in absorption at around 450–500 nm in the UV–vis spectrum representing the cis-isomer (Figure 1, black arrows). The absorption bands of the trans and cis-isomers of compounds 12a, 16c, and 16d overlap to

• indicated wavelength or by thermal relaxation (5a, 5b, 12a, 16a–d, 23, and 28). The irradiation times were determined by following the UV–vis spectrum upon isomerization until no more changes in absorption were observed and the photostationary state (PSS) was reached. The points of intersection in the