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Search for "absorption" in Full Text gives 912 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

  • Periklis X. Kolagkis,
  • Eirini M. Galathri and
  • Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

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Published 22 Feb 2024

Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

  • Carlos R. Azpilcueta-Nicolas and
  • Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

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  • absorption of light, an excited photocatalyst (*PC) engages in single-electron transfer (SET) with either donor (D) or acceptor (A) molecules (Scheme 3) [8][36]. Accordingly, a reductive quenching mechanism (path a) will operate when an excited photocatalyst effects the one-electron oxidation of a
  • (B2cat2) [63] (Scheme 15A). UV–vis absorption measurements showed that a mixture of a model NHPI ester with B2cat2 in dimethylacetamide (DMA) formed a new charge-transfer band in the visible region (>390 nm), which was attributed to the formation of EDA complex 74 (Scheme 15B). Under blue light
  • absorption spectra of PTH1 was observed, suggesting the formation of a charge transfer complex of the type 88 [68] (Scheme 17A). tert-Butyl radical (64), along with additional 2° and 3° alkyl radicals, resulting from these EDA complexes were harnessed in C(sp3)-heteroatom bond forming reactions [69], and in
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Perspective
Published 21 Feb 2024

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

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  • fragment gave rise to the appearance of an additional long-wavelength absorption band with λmax = 520 nm and ε = 9200 M−1⋅сm−1. Subjecting o-phenylenediamines 2с to the reaction with 3H-phenoxazin-3-one makes the simultaneous activation of two principle reaction pathways (SNH and Schiff base formation
  • successfully under the conditions applied to the preparation of 14H-quinoxaline[2,3-b]phenoxazines 5. The reaction proceeds readily with o-mercaptoaniline to produce the benzo[5,6][1,4]oxazino[2,3-b]phenothiazine derivative 10c (Scheme 6). Electronic absorption spectra of the prepared 14Н-quinoxaline[2,3-b
  • ]phenoxazines 5 and 6 (Table 2, Figures 5–7, and Figures S7–S11, Supporting Information File 1) exhibit broad and high-intensity absorption maxima in the range of 450–550 nm, which encompass the strongest emissive part of the solar spectrum. In contrast to nonfluorescent 6,8-di-tert-butyl-2-(arylamino)-3H
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Published 21 Feb 2024

Discovery of unguisin J, a new cyclic peptide from Aspergillus heteromorphus CBS 117.55, and phylogeny-based bioinformatic analysis of UngA NRPS domains

  • Sharmila Neupane,
  • Marcelo Rodrigues de Amorim and
  • Elizabeth Skellam

Beilstein J. Org. Chem. 2024, 20, 321–330, doi:10.3762/bjoc.20.32

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  • ]+ at m/z 773.4338, calculated for C41H57N8O7+, m/z 773.4345, Δ 0.9 ppm; [M + Na]+ at m/z 795.4162, calculated for C41H56N8O7Na+, m/z 795.4164, Δ 0.3 ppm) and NMR data analysis, corresponding to eighteen indices of hydrogen deficiency. Its UV spectrum exhibited absorption maxima at λmax 219 and 279 nm
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Published 19 Feb 2024

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

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  • stability. Conversely, selenepine 28c and selenepine Se-oxide 29c were quantitatively converted into the seco-HBC 31 by thermal activation at 200 °C for 5 min, as evidenced by UV–visible absorption and HPLC monitoring. SO-extrusion from thiepine S-oxide 29b was also successfully triggered in the solid state
  • dinaphthooxanorcaradiene bisimide valence isomer obtained upon electron injection and not its neutral form, as shown by UV–vis absorption and DFT studies. The mechanism of the final release of oxygen still remains unclear. This example shows that a careful molecular design allows endowing chalcogen heteropines with
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Published 15 Feb 2024

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

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  • 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
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Published 13 Feb 2024

Catalytic multi-step domino and one-pot reactions

  • Svetlana B. Tsogoeva

Beilstein J. Org. Chem. 2024, 20, 254–256, doi:10.3762/bjoc.20.25

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  • in the Full Research Paper by Nath and co-workers. The newly synthesized porphyrin derivatives displayed significant red-shifted absorption and emission compared to simple meso-tetraarylporphyrins [14]. The Carlone group reports an Enders-type triple cascade reaction toward cyclohexenals, using
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Editorial
Published 08 Feb 2024

Photochromic derivatives of indigo: historical overview of development, challenges and applications

  • Gökhan Kaplan,
  • Zeynel Seferoğlu and
  • Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

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  • -chromophores” after the shape of the main structural fragment resembling the Latin letter “H” (Figure 4) [19]. The small HOMO–LUMO gap and, thus, the long-wavelength absorption are responsible for the purple color of indigo in vapors, which changes into deep blue color in the crystalline state due to formation
  • color of these dyes, as shown by the absorption maxima positions of the substituted indigo derivatives (Table 1) [23][24]. The introduction of the ED (electron-donating) substituents into the para (5,5')- or ortho (7,7')-positions to the electron-donating NH group results in a bathochromic shift of the
  • absorption band and increases its intensity, while the presence of the EA (electron-accepting) substituents in these positions leads to a hypsochromic shift (Figure 5). On the contrary, the introduction of the ED substituents at the para (6,6')- or ortho (4,4')-positions to the electron-withdrawing C=O group
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Published 07 Feb 2024
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  • , the ensuing RE process yields the corresponding TCBD derivatives. The resulting TCBDs and related products exhibit strong light absorption, resulting from the intramolecular charge transfer (ICT) in the visible region; they also exhibit a rich redox chemistry [11]. In the [2 + 2] CA–RE reaction of
  • DCNQ unit or where a methyl group on the C60 surface is replaced by a hydrogen atom. The C60–TCBD conjugate 57 and C60–DCNQ conjugate 58 exhibited substantial optical rotations at 589 nm, presenting +770 for (P)-57 and +5,800 for (P)-58. In concordance, robust Cotton effects related to ICT absorption
  • particular, Diederich et al. conducted a theoretical investigation on the photophysical properties of 1,1,2,4,4-pentacyanobuta-1,3-diene (PCBD) (63) [134]. Compound 63 and the TCBD 64 demonstrated no discernible luminescence at room temperature and 77 K (Figure 4). Transient absorption spectral measurements
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Published 22 Jan 2024

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

  • Julika Schlosser,
  • Olga Fedorova,
  • Yuri Fedorov and
  • Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

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  • spectrometry. In all cases, the E-configuration of the alkene double bonds was indicated by characteristic coupling constants of the alkene protons (3JH–H = 16 Hz). Absorption properties and photoreactions of styrylpyridine derivatives In acetonitrile solution, the styrylpyridines 2a–g exhibited long
  • -wavelength absorption bands with maxima in a range from λmax = 333 nm for the ethyl-substituted compound 2f to λmax = 394 nm for the nitro-substituted derivative 2a (Figure 1A, Supporting Information File 1, Table S1). As compared with the absorption maximum of the parent compound at λmax = 330 nm [20], the
  • derivatives 2b–g showed a slight bathochromic shift mostly in the range of λmax = 333–360 nm, whereas for the nitro-substituted compound 2a a stronger red shift of the absorption maximum was observed, presumably caused by the strong electron-withdrawing property of the nitro group resulting in a more
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Published 18 Jan 2024

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

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  • absorption According to the Beer–Lambert law, the absorption of light in a solution can be described by Equation 1 [33]. where A is the absorbance, I0 is the intensity of light entering the solution perpendicularly to one face, Id is the intensity of light exiting the solution, ε is the extinction
  • shot under red light, which matched the absorption properties of the dye, to obtain optimal optical visualization. Digital images extracted from videos (see Supporting Information File 2) were processed with the Python OpenCV package to quantify the mixing time (see Supporting Information File 3
  • electronic absorption measurement Light attenuation in the reaction solution was measured for different optical paths (0.2, 0.5, 1, 2, 3, and 5 cm) with the same concentration of photocatalyst in water and methanol solution as used for photocatalytic hydrogen evolution. Cuvettes were used to model the
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Published 16 Jan 2024

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

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  • expanded by pyrrolo annelation. The optical and redox properties of these compounds, in some cases carbon-rich, were studied by UV–vis absorption spectroscopy and cyclic voltammetry. Synthetically, the work explores IF diones or fluorenone as central building blocks by subjecting the carbonyl groups to a
  • a subsequent Glaser–Hay coupling reaction, a RA acceptor unit was introduced to provide a DTF-IF-RA donor–acceptor scaffold with a low-energy charge-transfer absorption and multi-redox behavior. Keywords: alkynes; chromophores; fused-ring systems; heterocycles; redox chemistry; Introduction
  • could potentially after deprotonation be reacted with electrophiles as previously established [29] for the parent structure [30] without tert-butyl substituents. UV–vis absorption spectroscopy UV–vis absorption spectra of the known compound 4 [14] and new compounds 9–12 and 15 are depicted in Figure 3
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Published 15 Jan 2024

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

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  • dispersion. The polarizing optical microscopy (POM) images exhibited alignment of the DWCNTs along the shear direction (Figure 4a,b). To estimate the order parameter, the polarized optical absorption measurement was conducted at different sample angles ranging from 0° to 90° at intervals of 10° (Figure 4c
  • ). The sample rotation led to gradual changes in absorption intensities, and the average order parameter was calculated to be ≈0.23 from the spectra of 0° (A∥) and 90° (A⟂) using Equation 1 [21][23]. Generally, it is anticipated that rod-shaped particles with larger L/D will produce a highly aligned film
  • 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
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Published 11 Jan 2024

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

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  • 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
  • properties in chloroform solution revealed an absorption feature ranging from about 310 to 420 nm peaking at 360 ± 3 nm (with molar absorption coefficients (ε) between 4000 and 6000 L mol−1 cm−1) for all zwitterions except 2b and 2h (Figure 3 and Supporting Information File 1, Figure S82). Compounds 2b, the
  • Michael adduct of acrylamide, and 2h, the Michael adduct of 2-hydroxyethyl acrylate, show blue-shifted absorption maxima of 352 nm and 356 nm, respectively. Upon increasing the solvent polarity by using methanol instead of chloroform, a hypsochromic shift of the absorption maximum occurs (dotted lines in
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Published 10 Jan 2024

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

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  • similar to AA [12][13], indicating self-assembly via the hydrophobic effect and π-stacking interactions (Figure 3a,b). The self-assembly in water was further supported by UV–visible analysis, displaying slight red-shifts of the anthracene absorption bands relative to the spectrum in methanol (Δλmax = +3
  • guest-derived absorption bands around 340 nm and 420–650 nm, confirming the solubilization of C60 in water (Figure 4b). Similar host–guest composites were also obtained using PA-CH3, PA-OH, and PA-Im under the same conditions. It is noteworthy that the C60-solubilization efficiency varied depending on
  • showed broad, featureless absorption bands, with a characteristic small peak at ≈580 nm for the E22 transition only in the case of the s-CNT host–guest composite (Figure 4f,g) [24]. The concentration of GN in the aqueous solution of (PA-OCH3)n·(GN)m was estimated to be ≈0.03 mg mL−1. Amphiphile PA-OCH3
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Published 08 Jan 2024

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

  • Pavel S. Silaichev,
  • Tetyana V. Beryozkina,
  • Vsevolod V. Melekhin,
  • Valeriy O. Filimonov,
  • Andrey N. Maslivets,
  • Vladimir G. Ilkin,
  • Wim Dehaen and
  • Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

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  • (Mo Kα irradiation, graphite monochromator, ω-scans with 1° step at T = 295(2) K). Empirical absorption correction was applied. The structure was solved using the intrinsic phases in ShelXT program [24] and refined by ShelXL [25] using full-matrix least-squared method for non-hydrogen atoms. The H
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Published 05 Jan 2024

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

  • Nedra Touj,
  • François Mazars,
  • Guillermo Zaragoza and
  • Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

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  • observed for C2 when replacing its acidic proton with a CS2 group among all the nucleophilic carbene precursors that we have investigated so far [40][75]. Yet, we do not have an explanation for it. On IR spectroscopy, the most intense absorption in the ATR spectra of compounds 4a–c and 6a–f was always due
  • stretching vibration of the S=C–S− group, another strong absorption was clearly visible in the IR spectra of CAAC·CS2 betaines 4a–c. This second most intense band was observed around 1550 cm−1 (Table 2). It probably originated from the asymmetric stretching of the aldiminium group, in line with similar high
  • intensity bands previously observed at ca. 1528 and 1477 cm−1, respectively, in the IR spectra of imidazolinium and imidazolium inner salts [40]. Contrastingly, no remarkable absorption was detected in the IR spectra of triazolium derivatives 6a–f for the CNN or NNN motifs. Yet, in all the cases, medium
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Published 20 Dec 2023

Beyond n-dopants for organic semiconductors: use of bibenzo[d]imidazoles in UV-promoted dehalogenation reactions of organic halides

  • Kan Tang,
  • Megan R. Brown,
  • Chad Risko,
  • Melissa K. Gish,
  • Garry Rumbles,
  • Phuc H. Pham,
  • Oana R. Luca,
  • Stephen Barlow and
  • Seth R. Marder

Beilstein J. Org. Chem. 2023, 19, 1912–1922, doi:10.3762/bjoc.19.142

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  • potentials of the halides that can be reduced in this way, quantum-chemical calculations, and steady-state and transient absorption spectroscopy suggest that UV irradiation accelerates the reactions via cleavage of the dimers to the corresponding radical monomers. Keywords: dehalogenation; n-dopant
  • in THF are ca. 420 and 43 M−1 cm−1, respectively. Figure 3a and b show the absorption spectra of the two dimeric reductants in THF (see Supporting Information File 1, Figure S6 for data in toluene). (N-DMBI)2 shows a strong absorption feature with a maximum at 304 nm (εmax = 28000 M−1 cm−1) and a
  • bibenzoimidazole portion of the molecules to the C6H4NMe2 Y substituents (see Figure 3d and Supporting Information File 1, Figure S11). Most of the above-mentioned substrates exhibit little or no absorption at 365 nm (see Supporting Information File 1, Figure S4 for comparison of spectra of the reductants and BnBr
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Published 14 Dec 2023

Biphenylene-containing polycyclic conjugated compounds

  • Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

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  • ranging between 45% and 60%. The last step of the sequential reactions is the aromatization step and the target POAs 34a–c were obtained in yields between 80–84%. UV–vis investigations conducted on compounds 34a–c revealed absorption bands that align well with acene structures. While 34a and 34b displayed
  • nearly identical absorption profiles with a maximum absorption at λmax = 515 nm, the incorporation of donor groups in compound 34c led to a noteworthy bathochromic shift with a maximum absorption at λmax = 534 nm. Additionally, it was reported that all three compounds, 34a–c, demonstrated remarkable
  • )2C6H3, (c) H), followed by aromatization in acidic conditions, resulted in the formation of three [3]naphthalene regioisomers 43a–c, 44a–c, and 45a–c with excellent yields of up to 94%. The synthesized PAHs 43a, 44a, and 45a with diverse geometries exhibited interesting absorption and emission
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Published 13 Dec 2023

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

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  • -carbonitrile (REF) [5]. Absorption spectra of dilute toluene, tetrahydrofuran (THF), and chloroform solutions as well as of the films of compounds 6–9 are shown in Figure 2a,b. The nonstructured low-energy bands at wavelengths of 350–450 nm are well seen in the absorption spectra of 6–9. The wavelengths of
  • peaks of these low-energy absorption bands are collected in Table 1. A similar band was previously observed for REF [5]. On the basis of the results of the theoretical investigations, the low-energy absorption band of REF has been attributed to the intramolecular charge transfer (ICT) caused by electron
  • transfer from the donor to the acceptor. The absorption spectrum of REF is included in Figure 2a for comparison. Compounds 6–9 are characterized by similar absorption bands also caused by electron transfer from the 3,6-di-tert-butyl-9H-carbazole units to the pyridine-3,5-dicarbonitrile moiety. The number
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Published 12 Dec 2023

Controlling the reactivity of La@C82 by reduction: reaction of the La@C82 anion with alkyl halide with high regioselectivity

  • Yutaka Maeda,
  • Saeka Akita,
  • Mitsuaki Suzuki,
  • Michio Yamada,
  • Takeshi Akasaka,
  • Kaoru Kobayashi and
  • Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

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  • pressure and replaced with 1,2-dichlorobenzene (ODCB). The characteristic absorption peak at 1000 nm assigned to La@C2v-C82 decreased, and the new absorption peak at 934 nm assigned to the La@C2v-C82 anion increased. Reactions of the La@C2v-C82 anion with 4-methylbenzyl bromide (1a) were conducted at 110
  • °C for 2 h (Scheme 1). Figure 1 depicts the changes in the visible–near infrared (vis–NIR) absorption spectra during the reaction, showing gradual changes with isosbestic points. Since the electrolyte interferes with the high-performance liquid chromatography (HPLC) separation and anionic species may
  • absorption intensity ratio at 330 nm. On the other hand, no consumption of La@C2v-C82 was observed in the reaction of La@ C2v-C82 with 1a (Figure 2b). The reaction of the La@C2v-C82 anion toward 2a–5a requires heating, therefore the reactivity of La@C2vC82 anion is lower than that of the C602− and C60 anion
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Published 11 Dec 2023

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

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  • absorption and emission maxima of 411 and 520 nm, respectively, with a mega Stokes shift of 109 nm and fluorescence quantum yields both in the solid state (41%) and in solution (86%). The optical properties were supported by computational chemistry using density functional theory for optimized geometry and
  • absorption. A solution-processed OLED was fabricated using low turn-on voltage, which had performances with maximum power, current, and external quantum efficiencies of 6.70 lm/W, 10.6 cd/A, and 4.61%, respectively. Keywords: OLED; organoboron; solution processes; thienothiophene; triphenylamine
  • lithiation of 7 and following reaction with dimesitylboron fluoride in 85% yield (Scheme 1). Photophysical properties The UV–vis absorption and fluorescence spectra of DMB-TT-TPA (8) were recorded in THF (Figure 1 and Table 1) [38]. It showed maximum absorption and emission wavelengths of 411 and 520 nm
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Published 07 Dec 2023

Substituent-controlled construction of A4B2-hexaphyrins and A3B-porphyrins: a mechanistic evaluation

  • Seda Cinar,
  • Dilek Isik Tasgin and
  • Canan Unaleroglu

Beilstein J. Org. Chem. 2023, 19, 1832–1840, doi:10.3762/bjoc.19.135

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  • ), coupling constant, number of atoms. UV–vis absorption spectra were recorded on a Mapada Instruments UV3100PC spectrophotometer. Mass spectra were recorded on an Agilent 1200/6210 high-resolution mass time-of-flight (TOF) LC–MS spectrometer. Reactions were followed by thin-layer chromatography (TLC
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Published 06 Dec 2023

GlAIcomics: a deep neural network classifier for spectroscopy-augmented mass spectrometric glycans data

  • Thomas Barillot,
  • Baptiste Schindler,
  • Baptiste Moge,
  • Elisa Fadda,
  • Franck Lépine and
  • Isabelle Compagnon

Beilstein J. Org. Chem. 2023, 19, 1825–1831, doi:10.3762/bjoc.19.134

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  • approach is based on the IRMPD spectroscopic scheme (infrared multiple photon dissociation), which is the combination of mass spectrometry and IR spectroscopy. IRMPD is an action spectroscopy method that allows recording IR absorption spectra of isolated gas-phase ions, based on the measurement of the
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Published 05 Dec 2023

Selectivity control towards CO versus H2 for photo-driven CO2 reduction with a novel Co(II) catalyst

  • Lisa-Lou Gracia,
  • Philip Henkel,
  • Olaf Fuhr and
  • Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

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  • photosynthesis. Taking Nature as a model, the absorption of photons can drive electron-transfer processes, leading to the production of highly energetic molecules. By aiming at the conversion of CO2, a greenhouse gas implicated in climate change, the closure of the carbon cycle can be achieved [2]. For this
  • detect, if the two polymorphs show different catalytic activity, as in the following investigations the amorphic powder was used. Spectroscopic and electrochemical characterization The Co(II) complex 1 was characterized by UV–vis absorption spectroscopy in N,N-dimethylacetamide (DMA), as it was the
  • chosen solvent for photocatalysis. The absorption profile evokes the structured band of the free ligand BzQuTr [42], with two intense π–π* ligand-centered transitions at circa 319 nm and 330 nm (Figure 3). The pink solid dissolves as an intense blue DMA solution. Nevertheless, the d–d transitions
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Published 17 Nov 2023
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