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Search for "IR" in Full Text gives 1075 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Electrocatalytic hydrogenation of cyanoarenes, nitroarenes, quinolines, and pyridines under mild conditions with a proton-exchange membrane reactor

  • Koichi Mitsudo,
  • Atsushi Osaki,
  • Haruka Inoue,
  • Eisuke Sato,
  • Naoki Shida,
  • Mahito Atobe and
  • Seiji Suga

Beilstein J. Org. Chem. 2024, 20, 1560–1571, doi:10.3762/bjoc.20.139

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  • , entry 2). Pt/C afforded the best result (90% current efficiency, Table 3, entry 3). To increase the yield, the reaction was carried out until 4a was consumed. After 7 h of electrolysis (23.2 F mol−1), 4a was completely consumed and 5a was obtained in 82% yield. Although Ir/C was inefficient (Table 3
  • F mol−1 of electricity should be required ideally to reduce quinoline (6a) to 1,2,3,4-tetrahydroquinoline (7a), 4.0 F mol−1 of electricity was applied for the reactions. Pd/C, Ir/C, Ru/C, and Pt/C were used as cathode catalysts, and 3–5% yields of 7a were obtained by the use of each catalyst (Table
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Published 11 Jul 2024

Benzylic C(sp3)–H fluorination

  • Alexander P. Atkins,
  • Alice C. Dean and
  • Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 1527–1547, doi:10.3762/bjoc.20.137

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  • ]. Photoexcitation of the Ir(III) catalyst I with blue light resulted in the photoexcited Ir(III)* catalyst, which was capable of performing a single-electron reduction on N-acyloxyphthalimide, promoting decarboxylation, releasing CO2, a methyl radical, anionic phthalimide and an Ir(IV) species. The resultant methyl
  • radical displayed high affinity for benzylic HAT, in turn affording a benzylic radical and methane. The Ir(IV) species then oxidised the benzylic radical to the benzylic cation regenerating the ground-state iridium species, completing the catalytic cycle. Attack of the benzylic cation by fluoride, from
  • , generated from reduction of tert-butyl benzoperoxoate (TBPB), selective benzylic HAT afforded the benzylic radical. Subsequent oxidation by Ir(IV) generated the benzylic cation that could be trapped by fluoride to afford the benzyl fluorides. An impressive scope with broad functional group tolerance
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Published 10 Jul 2024

Tetrabutylammonium iodide-catalyzed oxidative α-azidation of β-ketocarbonyl compounds using sodium azide

  • Christopher Mairhofer,
  • David Naderer and
  • Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1510–1517, doi:10.3762/bjoc.20.135

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  • Research Center “RERI uasb”. All NMR spectra were referenced on the solvent residual peak (CDCl3: δ = 7.26 ppm for 1H NMR, δ = 77.16 ppm for 13C NMR,19F NMR unreferenced). IR spectra were recorded on a Bruker Alpha II FTIR spectrometer with diamond ATR-module using the OPUS software package. HRMS spectra
  • = 17.2 Hz, 1H), 2.99 (d, J = 17.2 Hz, 1H), 1.45 (s, 9H); 13C NMR (75 MHz, CDCl3, 298 K, δ/ppm) 198.1, 167.4, 152.3, 136.4, 133.3, 128.4, 126.5, 125.6, 84.6, 70.6, 38.6, 28.0; IR (neat, FT-ATR, 298 K, ν̃/cm−1): 2984, 2928, 2853, 2110, 1747, 1736, 1718, 1604, 1589, 1548, 1466, 1431, 1397, 1372, 1353, 1326
  • , 1H), 7.48 (t, J = 7.5 Hz, 1H), 4.11 (d, J = 17.9 Hz, 1H), 3.99 (d, J = 17.9 Hz, 1H), 1.49 (s, 9H); 13C NMR (126 MHz, CDCl3, 298 K, δ/ppm) 188.4, 162.0, 150.1, 137.0, 132.9, 129.1, 126.5, 126.2, 96.7, 86.1, 37.5, 27.8; IR (neat, FT-ATR, 298 K, ν̃/cm−1): 2984, 2930, 2878, 2854, 1748, 1719, 1656, 1604
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Published 05 Jul 2024

Towards an asymmetric β-selective addition of azlactones to allenoates

  • Behzad Nasiri,
  • Ghaffar Pasdar,
  • Paul Zebrowski,
  • Katharina Röser,
  • David Naderer and
  • Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1504–1509, doi:10.3762/bjoc.20.134

Graphical Abstract
  • Thermo Fisher Scientific LTQ Orbitrap XL spectrometer with an Ion Max API source and analyses were made in the positive ionization mode if not otherwise stated. Infrared (IR) spectra were recorded on a Bruker Alpha II FTIR spectrometer with diamond ATR-module using the OPUS software package and are
  • ), 3.52–3.16 (m, 4H), 1.15 (t, J = 7.1 Hz, 3H); 13C NMR (75 MHz, CDCl3, 298.0 K) δ/ppm = 177.4, 171.0, 160.3, 139.1, 133.8, 132.6, 130.5, 128.6, 128.0, 127.8, 127.3, 125.6, 118.1, 75.9, 60.9, 44.9, 39.3, 13.9; IR (neat): 3080, 3070, 2917, 1815, 1732, 1656, 1480, 1175, 1093, 1059, 1030, 974, 893, 694 cm−1
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Published 04 Jul 2024

Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA

  • Yu Fan,
  • Ahmed El Rhaz,
  • Stéphane Maisonneuve,
  • Emilie Gillon,
  • Maha Fatthalla,
  • Franck Le Bideau,
  • Guillaume Laurent,
  • Samir Messaoudi,
  • Anne Imberty and
  • Juan Xie

Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132

Graphical Abstract
  • was stirred at room temperature until total deprotection. The solution was neutralized using Amberlite IR-120 (H), filtered, concentrated and the crude material used without further purification to give the desired product in quantitative yield. (A) Selected monovalent inhibitors for PA LecA and (B
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Published 03 Jul 2024

Rapid construction of tricyclic tetrahydrocyclopenta[4,5]pyrrolo[2,3-b]pyridine via isocyanide-based multicomponent reaction

  • Xiu-Yu Chen,
  • Ying Han,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2024, 20, 1436–1443, doi:10.3762/bjoc.20.126

Graphical Abstract
  • , 58.2, 56.7, 55.2, 53.3, 52.2, 51.3, 50.4, 50.2, 32.4, 31.5, 31.2, 26.2, 25.7, 25.6, 18.2 ppm; IR (KBr) ν: 3435, 2931, 2862, 2360, 1737, 1698, 1587, 1547, 1435, 1385, 1335, 1251, 1204, 1125, 1092, 1001, 977, 895, 853, 792 cm−1; HRESIMS (m/z): [M + Na]+ calcd. for C41H46NaN2O11, 765.2994; found, 765.2993
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Published 28 Jun 2024

Generation of alkyl and acyl radicals by visible-light photoredox catalysis: direct activation of C–O bonds in organic transformations

  • Mithu Roy,
  • Bitan Sardar,
  • Itu Mallick and
  • Dipankar Srimani

Beilstein J. Org. Chem. 2024, 20, 1348–1375, doi:10.3762/bjoc.20.119

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  • the SET transfer process of PPh3 and quenching of photoexcited *[Ir(dF(CF3)ppy)2(bpy)]PF6 by PPh3. Fluorinated organic compounds are widely used in pharmaceuticals and pesticides. Therefore, it is crucial to diversify organic scaffolds by addition of fluorinated groups or by defluorination. In 2020
  • iridium photocatalyst [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 leads to excited-state *[Ir(III)], Ered (*[Ir(III)]/[Ir(II)]) = +1.21 V, possessing sufficient energy to oxidize PPh3, forming the triphenylphosphine radical cation. Subsequently, benzoic acid undergoes deprotonation facilitated by a base, producing
  • product. The photomediated formation of acyl radicals directly from acids mostly employs DMDC or phosphines (e.g., PPh3, PMe2Ph) as additives and [Ir(III)] as photocatalyst. In 2022, Chu and co-workers [32] developed a protocol to form acyl radicals directly from acids utilizing Ph2S as activator and the
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Published 14 Jun 2024
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  • in Flawil, Switzerland). The IR spectra were measured by Spectrum Two FT-IR spectrometer (PerkinElmer, Massachusetts, USA). The NMR spectra were measured using Bruker Ultrashield Plus Biospin 400 MHz NMR spectrometer and A600a Agilent DD2 600 MHz NMR spectrometer (Santa Clara, California, USA) and
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Published 06 Jun 2024

Mechanistic investigations of polyaza[7]helicene in photoredox and energy transfer catalysis

  • Johannes Rocker,
  • Till J. B. Zähringer,
  • Matthias Schmitz,
  • Till Opatz and
  • Christoph Kerzig

Beilstein J. Org. Chem. 2024, 20, 1236–1245, doi:10.3762/bjoc.20.106

Graphical Abstract
  • recent years was pioneered by the introduction of photocatalysts (PC) based on metals such as Ru and Ir [1][2][3][4][5][6]. However, due to the high cost and limited availability of precious metals, organic photocatalysts have become a focal point of academic and industrial research [7][8][9][10][11][12
  • to detect this species, as emphasized by Figure S5 and the discussion in Supporting Information File 1. Similarly, our attempts to identify 4CP•− in an analogous experiment that employed Ir(ppy)3 as a well-characterized reference photoreductant were also unsuccessful [73][74], probably due to an
  • established by Xu et al., but its success was limited to costly Ir-based photocatalysts. Lifetime-based quenching experiments of 3Aza-H with increasing cinnamyl chloride concentration revealed an energy transfer rate of 106 M−1 s−1 (Figure S9, Supporting Information File 1). Although this rate is four orders
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Published 28 May 2024

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

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  • -crystal X-ray structure refinement data for 3, 9, and 10. Single-crystal X-ray structure refinement data for 11, 12, and 13. Supporting Information Supporting Information File 64: Spectroscopic characterization of products (1H, 13C and 77Se NMR, IR, and HRMS spectra), packing arrangements of compounds
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Published 27 May 2024

Bismuth(III) triflate: an economical and environmentally friendly catalyst for the Nazarov reaction

  • Manoel T. Rodrigues Jr.,
  • Aline S. B. de Oliveira,
  • Ralph C. Gomes,
  • Amanda Soares Hirata,
  • Lucas A. Zeoly,
  • Hugo Santos,
  • João Arantes,
  • Catarina Sofia Mateus Reis-Silva,
  • João Agostinho Machado-Neto,
  • Leticia Veras Costa-Lotufo and
  • Fernando Coelho

Beilstein J. Org. Chem. 2024, 20, 1167–1178, doi:10.3762/bjoc.20.99

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  • first asymmetric catalytic Nazarov reaction [32]. In recent years, several strategies were reported employing different Lewis acids, such as, AuCl3/AgSbF6, Cu(II), In(OTf)3, Ir(III), Al(III), Sc(OTf)3/LiClO4, In(OTf)3/diphenylphosphoric acid (DPP), Fe(OTf)3/(CF3)2PhB(OH)2, iodine [33][34][35][36][37][38
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Published 21 May 2024

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

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  • 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

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  • 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

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  • -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

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  • 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

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  • 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

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  • 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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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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  • 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
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