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Search for "IR" in Full Text gives 1014 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Synthesis of 1,4-azaphosphinine nucleosides and evaluation as inhibitors of human cytidine deaminase and APOBEC3A

  • Maksim V. Kvach,
  • Stefan Harjes,
  • Harikrishnan M. Kurup,
  • Geoffrey B. Jameson,
  • Elena Harjes and
  • Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2024, 20, 1088–1098, doi:10.3762/bjoc.20.96

Graphical Abstract
  • the enzymatic assays and the synthesis of nucleosides and modified ODNs, assignment of 1H, 13C, 31P NMR and IR spectra and results of HRESIMS experiments for new compounds synthesised as well as RP-HPLC profiles and HRESIMS spectra of ODNs. Acknowledgements NMR and mass spectrometry facilities at
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Published 15 May 2024

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

Graphical Abstract
  • Evolution instruments (Horiba) with an excitation laser operated at 532 nm in the wavenumber range from 1000 to 2000 cm−1. FTIR spectra were obtained using an FT/IR-6600 (JASCO) in ATR method with a diamond prism. Magnetic susceptibility measurements were carried out by a superconducting quantum
  • to the more significant carrier scattering by introducing FeCp2 as a positively charged impurity caused by charge transfer with nanographene in FeCp2-ACFs-150. This is also supported by the increase in the linewidth of the G-band from 28 cm−1 (ACFs) to 31 cm−1 (FeCp2-ACFs-150). Figure 5 shows IR
  • ). Here, it should be noted that the vibrational spectra are more distorted due to electromagnetic shielding effects by the conductive nature of graphene-based materials upon IR excitation. Thus, the “apparent” negative absorption peak in the spectrum of FeCp2-ACFs-55 is caused by the phase shift of the
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Published 02 May 2024

Synthesis and properties of 6-alkynyl-5-aryluracils

  • Ruben Manuel Figueira de Abreu,
  • Till Brockmann,
  • Alexander Villinger,
  • Peter Ehlers and
  • Peter Langer

Beilstein J. Org. Chem. 2024, 20, 898–911, doi:10.3762/bjoc.20.80

Graphical Abstract
  • coupling constants J. Infrared spectra (IR) were measured as attenuated total reflection (ATR) experiments using a Nicolet 380 FT-IR spectrometer. The signals were characterized by their wavenumbers and corresponding absorption as very strong (vs), strong (s), medium (m), weak (w) or very weak (vw). UV–vis
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Published 22 Apr 2024

Synthesis of new representatives of A3B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations

  • Victoria M. Alpatova,
  • Evgeny G. Rys,
  • Elena G. Kononova and
  • Valentina A. Ol'shevskaya

Beilstein J. Org. Chem. 2024, 20, 767–776, doi:10.3762/bjoc.20.70

Graphical Abstract
  • carborane A3B-porphyrin were also synthesized based on the amino-substituted A3B-porphyrin. The structures of the prepared carboranylporphyrins were determined by UV–vis, IR, 1H, 19F, 11B NMR spectroscopic data and MALDI mass spectrometry. Keywords: bioconjugation; carboranes; fluorine; porphyrin; SNAr
  • easily converted into hydrophilic charged entities by the protonation of the unsubstituted amino functionalities in their structure providing improved bioconjugation. Spectroscopic data All porphyrin conjugates were structurally characterized by IR, UV–vis, NMR spectroscopy, and mass spectrometry. The IR
  • spectra of porphyrins 2 and 3 exhibit the absorption band at 3321 cm−1 corresponded to NН stretching vibrations. Bands at 2127 cm−1 confirmed the presence of the N3 group in porphyrins 2 and 7. The IR spectra of porphyrins 5–7, 11, 12, 14, 18–20, 23, 24, and 26 exhibit absorption bands at 2605–2609 cm−1
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Published 12 Apr 2024

Regioselective quinazoline C2 modifications through the azide–tetrazole tautomeric equilibrium

  • Dāgs Dāvis Līpiņš,
  • Andris Jeminejs,
  • Una Ušacka,
  • Anatoly Mishnev,
  • Māris Turks and
  • Irina Novosjolova

Beilstein J. Org. Chem. 2024, 20, 675–683, doi:10.3762/bjoc.20.61

Graphical Abstract
  • . Supporting Information File 60: Crystallographic information file (CIF) for compound 12a. Acknowledgements The authors thank Dr. chem. Kristīne Lazdoviča for IR analysis. Funding The authors thank the Latvian Council of Science Grant LZP-2020/1-0348 for financial support.
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Published 28 Mar 2024

Isolation and structure determination of a new analog of polycavernosides from marine Okeania sp. cyanobacterium

  • Kairi Umeda,
  • Naoaki Kurisawa,
  • Ghulam Jeelani,
  • Tomoyoshi Nozaki,
  • Kiyotake Suenaga and
  • Arihiro Iwasaki

Beilstein J. Org. Chem. 2024, 20, 645–652, doi:10.3762/bjoc.20.57

Graphical Abstract
  • procedures Optical rotations were measured with a JASCO DIP-1000 polarimeter. UV spectra were recorded on a UV-3600. ECD spectra were measured with JASCO J-1100. IR spectra were recorded on a Bruker ALPHA instrument. All NMR data were recorded on a JEOL ECX-400/ECS-400 spectrometer for 1H (400 MHz) and 13C
  • , MeOH); UV (MeOH) λmax, nm (log ε): 281 (2.27), 270 (2.96), 260 (2.40); ECD (100 μg/mL; MeOH), λmax, nm (Δε): 226 (−0.31), 274 (−0.76), 282 (−0.96); IR (neat): 3443, 2965, 2925, 2896, 1646, 1457, 1086 cm−1; HRESIMS (m/z): [M + Na]+ calcd for C44H66O15Na+, 857.4294; found, 857.4294. In vitro
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Published 21 Mar 2024

A laterally-fused N-heterocyclic carbene framework from polysubstituted aminoimidazo[5,1-b]oxazol-6-ium salts

  • Andrew D. Gillie,
  • Matthew G. Wakeling,
  • Bethan L. Greene,
  • Louise Male and
  • Paul W. Davies

Beilstein J. Org. Chem. 2024, 20, 621–627, doi:10.3762/bjoc.20.54

Graphical Abstract
  • -step ynamide annulation and imidazolium ring-formation sequence. Metalation with Au(I), Cu(I) and Ir(I) at the C2 position provides an L-shaped NHC ligand scaffold that has been validated in gold-catalysed alkyne hydration and arylative cyclisation reactions. Keywords: annulation; carbene; gold
  • fused imidazolium core (Scheme 2). No reaction was observed between 6a and [Ir(cod)Cl]2 in the presence of NEt3. A solution of the free carbene was prepared from 6 and reacted with [Ir(cod)Cl]2 and then CO to afford the AImOxIr(CO)Cl complex 15. A minor side-product with a strong red colour was formed
  • only two sharp CO stretching frequencies were observed in the IR (Scheme 2) and so a value for Tolman’s electronic parameter (TEP) could be estimated. [33] At TEP[Ir] = 2053.1 cm−1 and 2052.8 cm−1 for 15a and 15b, respectively, the values for these AImOx ligands are towards the electron-deficient end
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Published 18 Mar 2024

Chemical and biosynthetic potential of Penicillium shentong XL-F41

  • Ran Zou,
  • Xin Li,
  • Xiaochen Chen,
  • Yue-Wei Guo and
  • Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

Graphical Abstract
  • isolation of compound 3 (2.19 mg). Physical and spectroscopic data of compounds 1–3 Shentonin A (1): light green solid; [α]D20 +40.0 (c 0.17, CH3OH); UV (CH3OH) λmax, nm (log ε): 400 (3.45), 240 (4.24) nm; IR (KBr) νmax: 3347, 2960, 2926, 1688, 1654, 1612, 1260, 1078, 1021, 797 cm−1; for 1H NMR (CDCl3, 600
  • MHz) and 13C NMR (CDCl3, 125 MHz) spectral data, see Table 1; HRESIMS (m/z): [M − H]− calcd for 341.1870; found, 341.1862. Shentonin B (2): light green solid; [α]D20 +5.3 (c 0.07, CH3OH); UV (CH3OH) λmaxm nm (log ε): 280 (3.59), 220 (4.30) nm; IR (KBr) νmax: 3315, 2969, 1667, 1461, 1159, 1138, 1061
  • , 981, 914, 742 cm−1; for 1H NMR (CDCl3, 600 MHz) and 13C NMR (CDCl3, 125 MHz) spectral data, see Table 1; HRESIMS (m/z): [M − H]− calcd for 311.1765; found, 311.1755. Compound 3: transparent oily liquid; [α]D20 −46.7 (c 0.18, CH3OH); IR (KBr) νmax: 3432, 2960, 2923, 1762, 1450, 1260, 1180, 1016, 800 cm
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Published 15 Mar 2024

Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

  • Vladimir P. Rybalkin,
  • Sofiya Yu. Zmeeva,
  • Lidiya L. Popova,
  • Irina V. Dubonosova,
  • Olga Yu. Karlutova,
  • Oleg P. Demidov,
  • Alexander D. Dubonosov and
  • Vladimir A. Bren

Beilstein J. Org. Chem. 2024, 20, 552–560, doi:10.3762/bjoc.20.47

Graphical Abstract
  • were isolated preparatively and fully characterized by IR, 1H, and 13C NMR spectroscopy as well as HRMS and XRD methods. The reverse thermal reaction was catalyzed by protonic acids. N-Acylated compounds exclusively with Fe2+ formed nonfluorescent complexes with a contrast naked-eye effect: a color
  • )-ylidene)methyl)-N-(1,10-phenanthrolin-5-yl)-2-phenylacetamide (2c), a suspension of 1 in acetonitrile was boiled with phenylacetyl chloride until completely dissolved (Scheme 1 and Supporting Information File 1). The obtained compounds 2a–c existed as an N-acylated keto form. In the IR spectra, stretching
  • ], the signals of methine protons of E-isomers should be in the region of approximately 5.90 ppm [14]. Other IR, 1Н and 13С NMR spectroscopy and HRMS data confirming the structure of the synthesized compounds 1 and 2a–c are presented in Supporting Information File 2. Nonacylated compound 1 showed long
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Published 11 Mar 2024

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

  • Rattiya Janthanom,
  • Yuta Kikuchi,
  • Hiroki Kanto,
  • Tomoyasu Hirose,
  • Arisu Tahara,
  • Takahiro Ishii,
  • Arinthip Thamchaipenet and
  • Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

Graphical Abstract
  • ppm) in the 13C NMR spectra. Infrared (IR) spectroscopy was carried out using an FT-4600 Fourier transform infrared spectrometer (JASCO P-2200 Polarimeter, Japan). The UV spectra were measured using a SpectraMax QuickDrop micro-volume spectrophotometer (Molecular Devices, LLC., San Jose, USA) at
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Published 29 Feb 2024

(E,Z)-1,1,1,4,4,4-Hexafluorobut-2-enes: hydrofluoroolefins halogenation/dehydrohalogenation cascade to reach new fluorinated allene

  • Nataliia V. Kirij,
  • Andrey A. Filatov,
  • Yurii L. Yagupolskii,
  • Sheng Peng and
  • Lee Sprague

Beilstein J. Org. Chem. 2024, 20, 452–459, doi:10.3762/bjoc.20.40

Graphical Abstract
  • higher-boiling heptane. In this case, the desired product was isolated by double distillation at 7 °C in 50% yield and >90% purity and was fully characterized by 1H, 19F, 13C NMR and IR spectra. The presence of a characteristic band at 2038 cm−1 in the IR spectrum confirmed the allene structure of
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Published 27 Feb 2024

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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Review
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

Graphical Abstract
  • activation of NHPI esters under a photocatalytic oxidative quenching mechanism was reported for the first time by Glorius and co-workers in 2017 [46]. This activation mode was applied in the functionalization of styrenes using an Ir-photocatalyst and a diverse range of nucleophiles that are H-bond donors
  • oxidative quenching photocatalytic cycle employing Ir-based photoreductants and a Brønsted acid additive. While the interaction between the RAE 32 and diphenyl phosphoric acid involves hydrogen bonding, in analogy to the Glorius proposal, it is thought that the substrate activation occurs through proton
  • -coupled electron transfer (PCET), forming neutral radical species 33 and the corresponding phosphate conjugate base (Scheme 8B). The hypothesis is supported by an observed increase in the luminescence quenching of *Ir(p-CF3-ppy)3 by 32 in the presence of diphenyl phosphoric acid, as quantified by the
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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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  • short-term heating of the melted reactants at 220–250 °C is described, and the compounds were characterized by means of single-crystal X-ray crystallography, NMR, UV–vis, and IR spectroscopy, as well as cyclic voltammetry. The reaction with o-amino-, o-hydroxy-, and o-mercapto-substituted arylamines
  • 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
  • shifts were measured with a precision of 0.01 ppm, and 0.1 Hz for spin–spin coupling constants J. The assignment of resonance peaks was carried out using COSY, HSQC, and 1H,13C as well as 1H,15N HMBC. Melting points were determined using a PTP (M) apparatus and were left uncorrected. IR spectra were
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Published 21 Feb 2024

Chiral phosphoric acid-catalyzed transfer hydrogenation of 3,3-difluoro-3H-indoles

  • Yumei Wang,
  • Guangzhu Wang,
  • Yanping Zhu and
  • Kaiwu Dong

Beilstein J. Org. Chem. 2024, 20, 205–211, doi:10.3762/bjoc.20.20

Graphical Abstract
  • -catalyzed asymmetric hydrogenation of indoles to synthesize chiral indolines has been widely studied (Scheme 1a) [21][22]. Representative examples include Ir- or Ru-catalyzed asymmetric hydrogenation of 2,3,3-trisubstituted 3H-indole [23][24]. Generally, these methods employ precious metals and/or
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Published 01 Feb 2024

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

Graphical Abstract
  • solution such as the specific optical rotation [31][33][37][46][57][60][61][62][63], intensity of scattered light [33][37][57][58][60][62][64] or intensity of IR bands [31] against concentration for the presence of discontinuities. The concentrations corresponding to the discontinuities found are taken as
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Published 31 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

Graphical Abstract
  • effect on the yield of the final compounds 3 observed. The structures of compounds 3a–u were confirmed by IR, 1H and 13C NMR spectroscopy (Figures S1‒S44 in Supporting Information File 1) as well as by high-resolution mass spectrometry (HRMS). X-ray data obtained for compound 3g gave us final proof of
  • , 135.7, 143.8, 152.3, 152.9, 157.3, 162.4; IR (ATR, KBr, cm−1): ν 3402, 3316, 3201, 1700, 1688, 1649, 1629, 1594, 1568, 1520, 1497, 1476, 1454, 1444, 1426, 1386, 1358, 1335, 1311, 1276, 1264, 1248, 1194, 1090, 1057, 1028; HRMS–ESI-TOF (m/z): [M + H]+ calcd for C16H19N8O2+, 355.1625; found: 355.1628. (Z
  • , 174.5; IR (ATR, KBr, cm−1): ν 3400, 3359, 3255, 1625, 1602, 1563, 1554, 1508, 1495, 1483, 1455, 1436, 1425, 1402, 1385, 1356, 1332, 1319, 1303, 1283, 1257, 1215, 1151, 1095, 1067, 1053, 1035, 1011; HRMS–ESI-TOF (m/z): [M + H]+ calcd for C13H14N7S+, 300.1026; found, 300.1031. X-ray structure
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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

Graphical Abstract
  • 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
  • lower energies is a likely consequence of the greater donicity of CAACs and MICs vs NHCs. Hence, the ν̃ CS2 values recorded on IR spectroscopy constitute a more sensitive probe than the δ CS2 values obtained from 13C NMR spectroscopy to help discriminate the various types of dithiocarboxylate adducts
  • 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
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Published 20 Dec 2023

Construction of diazepine-containing spiroindolines via annulation reaction of α-halogenated N-acylhydrazones and isatin-derived MBH carbonates

  • Xing Liu,
  • Wenjing Shi,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1923–1932, doi:10.3762/bjoc.19.143

Graphical Abstract
  • spiro[indoline-3,5'-[1,2]diazepine]-6'-carboxylates 5a–g in 63–77% yields (Scheme 3). The substituents on both substrates also showed little effect on the yields. The chemical structures were fully characterized by HRMS, IR, 1H and 13C NMR spectra. For demonstrating the synthetic value of this protocol
  • , 125.5, 117.4, 109.9, 95.0, 52.3, 44.4, 37.0, 20.9 ppm; IR (KBr) ν: 2960, 2936, 2870, 2211, 1717, 1626, 1498, 1445, 1367, 1268, 1193, 1112, 1090, 1009, 903, 868, 815 cm−1; HRMS–ESI TOF (m/z): [M + Na]+ calcd for C34H26N4O2Na, 545.1956; found, 545.1948. General procedure for the preparation of
  • , 127.5, 127.0, 124.4, 111.6, 110.4, 52.2, 51.1, 44.4, 36.8 ppm; IR (KBr) ν: 2924, 2853, 1721, 1608, 1484, 1456, 1430, 1340, 1170, 812 cm−1; HRMS–ESI TOF (m/z): [M + H]+ calcd for C34H27ClN3O4, 576.1685; found, 576.1683. General procedure for the preparation of dihydrospiro[indoline-3,5'-[1,2]diazepines
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Published 18 Dec 2023

Biphenylene-containing polycyclic conjugated compounds

  • Cagatay Dengiz

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

Graphical Abstract
  • and iPrOH, resulting in the formation of compound 37 in 49% yield. In the final step, Ir-catalyzed cycloaddition reaction with diphenylacetylene (tolane) led to PAH 38 in 47% yield. According to the X-ray analysis results, it is evident that the structure of compound 38 is far from planarity, and the
  • phenanthrene moiety exhibits a dihedral angle of approximately 22°. Upon comparing the UV–vis spectra of the angular structures 37 and 38, it was observed that after the Ir-catalyzed cycloaddition reaction, the λmax of product 38 considerably blue shifted in comparison to the λmax of 37. Xia et al. also
  • 21. Synthesis of symmetric POAs 25a and 25b. Synthesis of POA 29 via palladium-catalyzed annulation/aromatization reaction. Synthesis of bisphenylene-containing structures 34a–c. Synthesis of curved PAH 38 via Pd-catalyzed annulation and Ir-catalyzed cycloaddition reactions. Synthesis of [3
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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

Graphical Abstract
  • dichloromethane (3 × 40 mL), washed with water, and brine. After evaporation of solvents the crude product was purified by flash chromatography on silica gel with DCM/petroleum ether 1:2 → 1:1. Derivative 6 was obtained as yellow powder (80 mg, 62%). Mp > 200 °C; IR νmax (film): 2227, 1550; 1H NMR (400 MHz, CDCl3
  • gel with dichloromethane/petroleum ether 1:1 → 2:1. Compound 7 was isolated as yellow powder (193 mg, 75%). Mp > 200 °C; IR νmax (film): 2228, 1602, 1538, 1530; 1H NMR (400 MHz, CDCl3) 8.12 (d, J = 2.0 Hz, 8H), 7.95–7.83 (m, 8H), 7.74 (d, J = 8.8 Hz, 8H), 7.72–7.64 (m, 8H), 7.50 (dd, J = 8.8, 2.0 Hz
  • was purified by flash chromatography on silica gel with chloroform/petroleum ether/acetone 9:15:0.4 by volume. The product 8 was obtained as orange powder (172 mg, 20%). Mp > 200 °C; IR νmax (film): 2252, 2240, 1538, 1532, 1425; 1H NMR (400 MHz, CDCl3) 8.11 (d, J = 2.0 Hz, 8H), 7.93–7.80 (m, 8H), 7.73
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Published 12 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

Graphical Abstract
  • intelligence in combination with spectroscopy-augmented mass spectrometry for carbohydrates sequencing and glycomics applications. Keywords: Bayesian neural network; deep learning; glycomics; IR; spectroscopy; Introduction DNA and protein sequencing technologies that aim at determining the structure of a
  • spectrometry (MS). In short, our technology is based on a mass spectrometric analysis – which is particularly powerful for the analysis of complex biological samples but does not readily elucidate isomers which have the same molecular mass – augmented with a infrared laser-based spectroscopic dimension (MS–IR
  • ), thus providing valuable additional isomer resolution [4]. We demonstrated that this multidimensional MS–IR molecular fingerprint is unique to each carbohydrate building block and can be used to resolve their full sequence, including their monosaccharide content and the detail of their linkages
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Published 05 Dec 2023

A novel recyclable organocatalyst for the gram-scale enantioselective synthesis of (S)-baclofen

  • Gyula Dargó,
  • Dóra Erdélyi,
  • Balázs Molnár,
  • Péter Kisszékelyi,
  • Zsófia Garádi and
  • József Kupai

Beilstein J. Org. Chem. 2023, 19, 1811–1824, doi:10.3762/bjoc.19.133

Graphical Abstract
  • from commercially available sources (Merck, TCI Europe, and VWR). Infrared (IR) spectra were recorded on a Bruker Alpha-T Fourier-transform IR (FTIR) spectrometer. Optical rotations were measured on a Perkin Elmer 241 polarimeter calibrated by measuring the optical rotations of both enantiomers of
  • further purifications. TLC (SiO2; DCM/MeOH/25% NH4OH(aq) 10:1:0.01, Rf 0.22); mp 158–160 °C; −51.8 (c 1.00, DMSO); IR (cm−1) νmax: 2957, 2923, 2853, 1664, 1620, 1609, 1560, 1508, 1437, 1378, 1331, 1277, 1201, 1175, 1126, 1021, 930, 884, 832, 799, 719, 700, 679, 620, 550, 521, 414; 1H NMR (500 MHz, MeOH
  • was dissolved in a small amount of dichloromethane (1 mL) and added dropwise to acetonitrile (100 mL) to precipitate the product as an off-white solid (698 mg, 58%). TLC (SiO2, DCM/MeOH 20:1, Rf 0.35); mp 68–69 °C; +14.1 (c 1.00, CHCl3); IR (cm−1) νmax: 3267, 2916, 2850, 1792, 1689, 1622, 1604, 1587
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Published 24 Nov 2023

Recent advancements in iodide/phosphine-mediated photoredox radical reactions

  • Tinglan Liu,
  • Yu Zhou,
  • Junhong Tang and
  • Chengming Wang

Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131

Graphical Abstract
  • utilities, there are still a few drawbacks associated with these photoredox reactions. One of the main limitations is the reliance on precious metals such as Ir, Ru, and Pd, or elaborate organic dyes that act as photosensitizers, which are either limited in abundance or require additional synthetic steps to
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Published 22 Nov 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

Graphical Abstract
  • associated with this absorption centered at 615 nm possess a low molar extinction coefficient (ε ≈ 220 cm−1 M−1, inset in Figure 3). Infrared (IR) spectroscopy was performed via attenuated total reflectance (ATR) and showed the characteristic stretching vibration of the NCS groups at 2069 cm−1 (Figure S3 in
  • removed under reduced pressure and the crude product was washed with cold MeOH and Et2O, obtaining a lilac precipitate (82 mg, 0.11 mmol, 60%). Paramagnetic properties were estimated by the Evans method [56] in acetonitrile and resulted in three unpaired electrons. ATR–IR (cm−1) ν: 3109, 3027, 2065, 1606
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Published 17 Nov 2023
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