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Search for "ACID" in Full Text gives 3047 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Structure and thermal stability of phosphorus-iodonium ylids

  • Andrew Greener,
  • Stephen P. Argent,
  • Coby J. Clarke and
  • Miriam L. O’Duill

Beilstein J. Org. Chem. 2024, 20, 2931–2939, doi:10.3762/bjoc.20.245

Graphical Abstract
  • Information File 1, Figure S6), the Kamlet–Taft hydrogen bond acceptor ability (β) (Supporting Information File 1, Figure S7) [37], the pKa of the conjugate acid HX (Figure S8), or the anion’s position (axial vs equatorial). The main stabilising factor we identified was the torsion angle φ between the
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Published 14 Nov 2024

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

  • Ritu Mamgain,
  • Kokila Sakthivel and
  • Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

Graphical Abstract
  • decarboxylation of α,α-difluoro-β-keto acid esters 11 with the help of aryl(TMP)iodonium tosylates 12 in toluene at 100 °C to yield α,α-difluoroketones 13 in excellent yield (Scheme 4). The reaction proceeds via ligand exchange between the fluorinated carboxylate and the tosylate anion of the hypervalent iodine
  • factors like steric hindrance. The ring opening proceeded smoothly when nucleophiles with higher nucleophilicity are used yielding up to 99% of the desired products 43. The N-arylation of amino acid esters 44 was established with the utility of substituted phenyl(anisyl)iodonium triflate salts 45 (Scheme
  • trifluoromethanesulfonate with p-toluic acid in the presence of t-BuOH. Moreover, later in 2022 Chen et al. modified the aromatic ring of gemfibrozil (69) and its methyl ester using gemfibrozil-derived diaryliodonium salts 72 synthesized by the aforementioned procedure [79]. On reacting gemfibrozil 69 in the presence of
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Review
Published 13 Nov 2024

C–H Trifluoromethylthiolation of aldehyde hydrazones

  • Victor Levet,
  • Balu Ramesh,
  • Congyang Wang and
  • Tatiana Besset

Beilstein J. Org. Chem. 2024, 20, 2883–2890, doi:10.3762/bjoc.20.242

Graphical Abstract
  • AgSCF3. Finally, to further illustrate the synthetic utility of the trifluoromethylthiolated hydrazones, product 2g was further functionalized. In the presence of 4-methylboronic acid, the arylation of 2g occurred and the expected product was isolated in 72% yield with the SCF3-hydrazone motif remaining
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Published 12 Nov 2024

Synthesis of pyrrole-fused dibenzoxazepine/dibenzothiazepine/triazolobenzodiazepine derivatives via isocyanide-based multicomponent reactions

  • Marzieh Norouzi,
  • Mohammad Taghi Nazeri,
  • Ahmad Shaabani and
  • Behrouz Notash

Beilstein J. Org. Chem. 2024, 20, 2870–2882, doi:10.3762/bjoc.20.241

Graphical Abstract
  • gloves with high chemical resistance. The reactions should be carried out in a hood with a strong suction and with a protective explosion shield, which in this test should be as low as possible. Since exposure to water and strong acids leads to the formation of hydrazoic acid, which is very toxic
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Published 11 Nov 2024

N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity

  • Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240

Graphical Abstract
  • , and Parkinson's disease, cardiovascular diseases, inflammation, AIDS and others have their origin in context with the activities of protein kinases, such as glycogen synthase kinase-3 (GSK-3β) and cyclin-dependent kinases (CDK’s). The phosphorylation of the amino acid moieties of several enzymes is
  • precursors. The base-mediated reaction of 5-chloroanthranilic acid (8a) with chloroacetic acid afforded 8b (Scheme 5) [20]. Acetylation and base-mediated cyclization gave indoxyl 9a which was transformed to indigo 1c by oxidative dimerization. Benzylation finally afforded 1d. 4,6-Benzylidenation of ᴅ
  • steps from indigo (1a). The reaction of 1a with potassium permanganate afforded product 12 which was transformed to dehydroindigo (13) by pyridine-mediated elimination of acetic acid. The reaction of 13 with tetra-O-trimethylsilyl-ʟ-rhamnopyranose (4b) in the presence of trimethylsilyl iodide, addition
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Published 08 Nov 2024

Synthesis of tricarbonylated propargylamine and conversion to 2,5-disubstituted oxazole-4-carboxylates

  • Kento Iwai,
  • Akari Hikasa,
  • Kotaro Yoshioka,
  • Shinki Tani,
  • Kazuto Umezu and
  • Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2024, 20, 2827–2833, doi:10.3762/bjoc.20.238

Graphical Abstract
  • ,O-acetal derived from diethyl mesoxalate (DEMO) undergoes elimination of acetic acid upon treatment with a base, leading to the formation of N-acylimine in situ. Lithium acetylide readily attacks the imino group to afford N,1,1-tricarbonylated propargylamines. When the resulting propargylamine
  • reacts with butyllithium, ring closure occurs between the ethynyl and carbamoyl groups, yielding 2,5-disubstituted oxazole-4-carboxylates. This cyclization also occurs when the propargylamine is heated with ammonium acetate, resulting in double activation. Keywords: acid amide; diethyl mesoxalate; N
  • esters and N-acyl groups is limited to acetyl, benzoyl, and alkoxycarbonyl groups [15]. Conversely, NAIs derived from α-oxomalonic acid diester are more versatile. Nagao et al. prepared NAI 2 through the aza-Wittig reaction of diethyl mesoxalate (DEMO, diethyl α-oxomalonate). However, only the N-acetyl
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Published 06 Nov 2024

Investigation of a bimetallic terbium(III)/copper(II) chemosensor for the detection of aqueous hydrogen sulfide

  • Parvathy Mini,
  • Michael R. Grace,
  • Genevieve H. Dennison and
  • Kellie L. Tuck

Beilstein J. Org. Chem. 2024, 20, 2818–2826, doi:10.3762/bjoc.20.237

Graphical Abstract
  • , highly sensitive chemosensors via a facile synthetic route/method, we have explored three chelates for lanthanide ions (DO3A, 2,6-pyridinedicarboxylic acid and DO2A), resulting in complexes with different overall charges. Additionally we have explored two copper(II) binding groups (di(2-picolyl)amine and
  • removal of Na2S followed by the precipitation and re-addition of Cu2+ ions (Figure 5). Comprehensive selectivity studies were conducted with various anions/sulfur compounds (SO42−, SO32−, S2O52−, S2O42−, S2O32−, ClO−, OAc−, NO3−, I−, HCO3−, CO32−, Cl−, lipoic acid, and glutathione, as depicted in Figure 6
  • ). It was interesting to note that neither of the sulfur-containing compounds caused a remarkable increase in luminescence, especially lipoic acid and glutathione which contain an –S–S (pKa = 4.7) and –SH (pKa = 9.65) group respectively similar to HS−(aq) (pKa = 6.9). This demonstrates that the sensors
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Published 05 Nov 2024

Synthesis and antimycotic activity of new derivatives of imidazo[1,2-a]pyrimidines

  • Dmitriy Yu. Vandyshev,
  • Daria A. Mangusheva,
  • Khidmet S. Shikhaliev,
  • Kirill A. Scherbakov,
  • Oleg N. Burov,
  • Alexander D. Zagrebaev,
  • Tatiana N. Khmelevskaya,
  • Alexey S. Trenin and
  • Fedor I. Zubkov

Beilstein J. Org. Chem. 2024, 20, 2806–2817, doi:10.3762/bjoc.20.236

Graphical Abstract
  • acid or pure acetic acid [25][26][27][28][34][35][36]. Within the framework of this study, the primary task was to establish the optimal reaction conditions for the interaction of 2-aminoimidazole (1) with N-phenylmaleimide (2a) (Scheme 1). The choice of the investigated reaction conditions was based
  • ) Superposition of docked compounds 4a–e and 5e in a CYP51 ACb. aThe amino acid residues of the protein are colored green, compound 4e is colored gold and the haem is colored grey. The heterocyclic nitrogen of compound 5e appears to be orientated towards iron and is located 2.8 Å away from it, which may indicate
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Published 05 Nov 2024

C–C Coupling in sterically demanding porphyrin environments

  • Liam Cribbin,
  • Brendan Twamley,
  • Nicolae Buga,
  • John E. O’ Brien,
  • Raphael Bühler,
  • Roland A. Fischer and
  • Mathias O. Senge

Beilstein J. Org. Chem. 2024, 20, 2784–2798, doi:10.3762/bjoc.20.234

Graphical Abstract
  • the Suzuki coupling began with investigating first the Suzuki reaction compatibility of boronic acid 14 with porphyrin 13. Porphyrin 13 and phenylboronic acid (14) were subjected to coupling at 85 °C for 48 hours using Pd2dba3/SPhos as a catalyst/ligand giving porphyrin 26 in a 32% yield, based on a
  • their steric bulk (e.g., 9-anthracenylboronic acid (15)). Table 1 lists all attempts at the meso-para-phenyl position. When attempting the synthesis of tetra(p-phenylanthracene)porphyrin (27) the conditions used before (Table 1, entry 1) resulted only in trace amounts of porphyrin 27 (Table 1, entry 2
  • ). The reaction temperature was increased to 110 °C, affording the desired porphyrin 27 in a 39% yield (Table 1, entry 3). A temperature of 110 °C was also used for the synthesis of terphenylporphyrin 28 using boronic acid 17, affording terphenylporphyrin 28 in 48% yield (Table 1, entry 7). Boronic acids
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Published 04 Nov 2024

Access to optically active tetrafluoroethylenated amines based on [1,3]-proton shift reaction

  • Yuta Kabumoto,
  • Eiichiro Yoshimoto,
  • Bing Xiaohuan,
  • Masato Morita,
  • Motohiro Yasui,
  • Shigeyuki Yamada and
  • Tsutomu Konno

Beilstein J. Org. Chem. 2024, 20, 2776–2783, doi:10.3762/bjoc.20.233

Graphical Abstract
  • a smooth [1,3]-proton shift reaction with a high chirality transfer, affording the corresponding rearranged products in acceptable yields. Without purification, these products were subjected to acid hydrolysis and the subsequent N-Cbz protection, providing the optically active tetrafluoroethylenated
  • published that the asymmetric conjugate addition of 4-methylphenylboronic acid towards (E)-5-bromo-4,4,5,5-tetrafluoro-1-phenyl-2-penten-1-one (8) in the presence of a rhodium catalyst coordinated with (S)-BINAP gave the corresponding Michael adduct 9 in 94% enantiomeric excess (reaction 2, Scheme 1) [22
  • ]-proton shift reaction of various tetrafluoroethylenated imines. Results and Discussion The preparation of substrates used in this study was as outlined in Scheme 3. Namely, the zinc reagent was prepared from commercially available 3,3,4,4-tetrafluoro-1-butene (18) [33] and reacted with various acid
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Published 01 Nov 2024

Copper-catalyzed yne-allylic substitutions: concept and recent developments

  • Shuang Yang and
  • Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

Graphical Abstract
  • alkoxylation and alkylation products with the assistance of Lewis acid as co-catalyst (Scheme 9). Starting from four different racemic substrates, the same product 6g with 96% ee was obtained under standard conditions. This indicates that the reactions proceed through the same transition state and the
  • as Meldrum’s acid and 1,3-dimethylbarbituric acid were used as the nucleophiles, the yne-allylic substitution products underwent further intramolecular cyclizations to give the spiro-cyclic products in high yields (Scheme 31, 30a–f). The generation of products likely begins with an α-attack on the
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Review
Published 31 Oct 2024

Interaction of a pyrene derivative with cationic [60]fullerene in phospholipid membranes and its effects on photodynamic actions

  • Hayato Takagi,
  • Çetin Çelik,
  • Ryosuke Fukuda,
  • Qi Guo,
  • Tomohiro Higashino,
  • Hiroshi Imahori,
  • Yoko Yamakoshi and
  • Tatsuya Murakami

Beilstein J. Org. Chem. 2024, 20, 2732–2738, doi:10.3762/bjoc.20.231

Graphical Abstract
  • , respectively. In this study, by mimicking our previous system of triad molecules and living cells, we report a simplified model system with a cationic C60 derivative (catC60) and a liposome with embedded 1-pyrenebutyric acid (PyBA) to demonstrate that the addition of PyBA was important to achieve fast and
  • ) liposomes of 1,2-dimyristoyl-sn-glyreco-3-phosphocholine (DMPC, Figure 1d), a well-known model of the plasma membrane, (ii) a cationic derivative of C60 (catC60, Figure 1e) as a replacement of the triad molecules, and (iii) 1-pyrenebutyric acid (PyBA, Figure 1f) as an anchor molecule for catC60 to be
  • present study for controlling both the location and photodynamic actions of a cationic derivative of C60 (catC60), a simple model compound of the triad molecules, in a membrane via π–π interactions with 1-pyrenebutyric acid (PyBA). (d–f) Chemical structures of 1,2-dimyristoyl-sn-glycero-3-phosphocholine
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Letter
Published 30 Oct 2024

Synthesis of spiroindolenines through a one-pot multistep process mediated by visible light

  • Francesco Gambuti,
  • Jacopo Pizzorno,
  • Chiara Lambruschini,
  • Renata Riva and
  • Lisa Moni

Beilstein J. Org. Chem. 2024, 20, 2722–2731, doi:10.3762/bjoc.20.230

Graphical Abstract
  • the acid-catalyzed [4 + 1] cycloaddition of commercially available substrates, as indoles and nitroalkenes to give spiro-isoxazoles (Scheme 1c), but acceptable yields were obtained just using nitrostyrenes [13][14]. Despite these examples, the highly efficient construction of structurally diverse
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Published 29 Oct 2024

Synthesis of benzo[f]quinazoline-1,3(2H,4H)-diones

  • Ruben Manuel Figueira de Abreu,
  • Peter Ehlers and
  • Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2708–2719, doi:10.3762/bjoc.20.228

Graphical Abstract
  • and Suzuki–Miyaura cross-coupling reactions followed by Brønsted acid-mediated cycloisomerisation. The developed methodology tolerates various functional groups and leads to moderate up to quantitative yields of the final products. The impact of different functional groups on the optical properties
  • of palladium-catalysed Sonogashira–Hagihara and Suzuki–Miyaura cross-coupling reactions (Scheme 1). The final cyclisation step is accomplished by an acid-mediated cycloisomerisation. The synthesis of starting materials 4 was carried out by our previously reported protocol [65]. While compounds 4a–f
  • are known compounds, the synthesis of derivatives 4g–i has not been previously reported (Scheme 2). Yields were generally lower in case of the presence of electron-withdrawing substituents. Subsequently, the cyclisation of 4a–i to 5a–i by acid-mediated cycloisomerisation was studied. In our first
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Published 28 Oct 2024

5th International Symposium on Synthesis and Catalysis (ISySyCat2023)

  • Anthony J. Burke and
  • Elisabete P. Carreiro

Beilstein J. Org. Chem. 2024, 20, 2704–2707, doi:10.3762/bjoc.20.227

Graphical Abstract
  • Suzuki couplings and the reduction of the thiazole moiety to 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines, a crucial intermediate, using BH3⋅NH3 and tris(pentafluorophenyl)borane as a Lewis acid, followed by treatment with formic acid. Gillie et al. reported the synthesis of a laterally fused N-heterocyclic
  • in MeOH at room temperature with a short reaction time. Some of them were further functionalized with a 1,2,3-triazole ring via copper-catalyzed azide–alkyne cycloaddition (CuAAC) and deprotected with trifluoroacetic acid. Several hybrids were evaluated against six cancer cell lines, displaying GI50
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Editorial
Published 28 Oct 2024

Synthesis of fluoroalkenes and fluoroenynes via cross-coupling reactions using novel multihalogenated vinyl ethers

  • Yukiko Karuo,
  • Keita Hirata,
  • Atsushi Tarui,
  • Kazuyuki Sato,
  • Kentaro Kawai and
  • Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 2691–2703, doi:10.3762/bjoc.20.226

Graphical Abstract
  • First, we optimized the conditions of the Suzuki–Miyaura cross-coupling in reference to the report by Yang et al. (Table 1) [43]. Upon the treatment of multihalogenated vinyl ether 1a with phenylboronic acid 4a (1.3 equiv) and palladium diacetate (10 mol %) as a catalyst at 40 °C, Suzuki–Miyaura cross
  • investigated using various boronic acids 4 and alkynes 5 in cross-coupling reactions using 1 (Table 3 and Table 4). p-Tolylboronic acid 4b provided 2b quantitatively, whereas m- and o-tolylboronic acids 4c and 4d produced 2c and 2d in low yields because the methyl group was positioned near the reaction site
  • % yields (Table 3, entries 6–8). The reaction between 1a and 4j, which contains an electron-withdrawing nitro group, afforded 2j in 88% yield (Table 3, entry 9). Although p-hydroxyphenylboronic acid (4k) gave 2k in only 9% yield, m-aminophenylboronic acid (4l) provided 2l in high yield (Table 3, entries 10
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Published 24 Oct 2024

Computational design for enantioselective CO2 capture: asymmetric frustrated Lewis pairs in epoxide transformations

  • Maxime Ferrer,
  • Iñigo Iribarren,
  • Tim Renningholtz,
  • Ibon Alkorta and
  • Cristina Trujillo

Beilstein J. Org. Chem. 2024, 20, 2668–2681, doi:10.3762/bjoc.20.224

Graphical Abstract
  • colleagues [1]. These compounds, which feature a Lewis acid (LA) and a Lewis base (LB), whose interaction is hindered by bulky substituents or chain strain, have garnered significant attention. Initially explored for their ability to trap small molecules [2][3], such as H2 [4], CO2 [5][6][7], N2O [8][9], and
  • , depicted by the purple points in Figure 1B. Results and Discussion The following nomenclature will be used during the volcano plot analysis: FX_LBLA_S1_S2 where X is the label of the family (1, 2, 3, 5, or 6), LB is the Lewis base considered (N or P), LA is the Lewis acid (in this particular study only B
  • results, we looked into the literature to explore examples of asymmetric FLPs. This exploration revealed three main types, namely, intramolecular chiral FLPs, intermolecular FLPs composed of a chiral acid and an achiral base, and intermolecular FLPs comprising an achiral acid and a chiral base [61][62
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Published 22 Oct 2024

Transition-metal-free decarbonylation–oxidation of 3-arylbenzofuran-2(3H)-ones: access to 2-hydroxybenzophenones

  • Bhaskar B. Dhotare,
  • Seema V. Kanojia,
  • Chahna K. Sakhiya,
  • Amey Wadawale and
  • Dibakar Goswami

Beilstein J. Org. Chem. 2024, 20, 2655–2667, doi:10.3762/bjoc.20.223

Graphical Abstract
  • mmol) and mandelic acid derivatives 2a–d (6 mmol) was stirred and heated to 50 °C under nitrogen atmosphere until the mixture turned into a viscous oil. The viscous oil/paste was further heated to 140 °C until the reaction was complete (cf. TLC). The mixture was then brought to room temperature and a
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Published 21 Oct 2024

The scent gland composition of the Mangshan pit viper, Protobothrops mangshanensis

  • Jonas Holste,
  • Paul Weldon,
  • Donald Boyer and
  • Stefan Schulz

Beilstein J. Org. Chem. 2024, 20, 2644–2654, doi:10.3762/bjoc.20.222

Graphical Abstract
  • various lipid classes including sterols, triacylglycerols, and common fatty acid methyl esters [15]. Mass spectrometric analysis of the lipid content of crotalines, mainly the Western Diamondback Rattlesnake (C. atrox), confirmed the presence of cholesterol [3][6][11][16], fatty acids [11], fatty amides
  • , Figure S1), confirming the acid functional group in the natural compounds. In support of these data, GC/IR analysis of Dm (Supporting Information File 1, Figure S2) showed strong carbonyl bands at 1741 cm−1 accompanied by two intermediate bands at 1198 cm−1 and 1177 cm−1, characteristic of ester valence
  • gap between m/z 192 and 232 indicates a methyl group either at either C-5 or C-6. Taken together, the data from the derivatizations led to the conclusion that one methyl group is located at C-4 and a second at C-6. This is consistent with regular fatty acid biosynthesis of mid-chain methyl
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Published 18 Oct 2024

Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels

  • Connor R. M. MacDonald and
  • Emily R. Draper

Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220

Graphical Abstract
  • structures formed by the self-assembly of amino acid-appended perylene bisimides (PBIs) [83]. They found that the average fibre length was a critical nanostructural feature for affording a desirable mechanoresponsive property, that is the change in conductivity under a bending force, in PBI films. Therefore
  • was achieved by Firipis et al. where they used SAXS to quantify hydrogels formed from self-assembling bioactive peptides Fmoc-DIKVAV and Fmoc-FRGDF (D = aspartic acid, I = isoleucine, K = lysine, V = valine, A = alanine, F = phenylalanine, R = arginine, G = glycine) [88]. The physical characteristics
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Published 16 Oct 2024

Efficient modification of peroxydisulfate oxidation reactions of nitrogen-containing heterocycles 6-methyluracil and pyridine

  • Alfiya R. Gimadieva,
  • Yuliya Z. Khazimullina,
  • Aigiza A. Gilimkhanova and
  • Akhat G. Mustafin

Beilstein J. Org. Chem. 2024, 20, 2599–2607, doi:10.3762/bjoc.20.219

Graphical Abstract
  • as 6-methyluracil (MU), 1,3,6-trimethyluracil (TMU), and pyridine (Py), and the results of the experiments are presented in this article. The hydroxy derivatives of MU and Py, obtained through oxidation followed by acid hydrolysis, possess compelling biological properties, rendering them practically
  • 2 was no more than 15%. Subsequently, upon acid hydrolysis of compound 2, HMU (3) was produced. The addition of PcM to the reaction mixture resulted in a significant increase in the yield of compound 2 [13][22]. The catalysts were added in quantities ranging from 0.00001–0.1 wt %, with the amount of
  • derivatives). Our study marks the first time pyridine has been involved in the peroxydisulfate oxidation reaction. The oxidation of pyridine (7) using APS resulted in a single product – pyridin-2-yl ammonium sulfate (8). Upon acid hydrolysis, this product yielded HPy (9, Scheme 2). The physicochemical and
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Published 16 Oct 2024

Base-promoted cascade recyclization of allomaltol derivatives containing an amide fragment into substituted 3-(1-hydroxyethylidene)tetronic acids

  • Andrey N. Komogortsev,
  • Constantine V. Milyutin and
  • Boris V. Lichitsky

Beilstein J. Org. Chem. 2024, 20, 2585–2591, doi:10.3762/bjoc.20.217

Graphical Abstract
  • purification. The synthetic utility of the prepared tetronic acids was demonstrated by further transformations at the hydroxyethylidene fragment. The structures of one obtained tetronic acid and one product of derivatization were confirmed by X-ray analysis. Keywords: allomaltol; base-promoted recyclization
  • ; 1,1′-carbonyldiimidazole; 3-hydroxypyran-4-ones; tetronic acid; Introduction 3-Hydroxypyran-4-one derivatives are an important class of heterocyclic compounds widely represented in various naturally occurring sources [1][2][3][4]. Products of this type demonstrate a broad range of biological activity
  • [5][6][7][8][9][10][11][12][13]. For example, 2-hydroxymethyl-5-hydroxypyran-4-one (kojic acid) is a well-known skin whitening agent extensively used in the cosmetic, medicine and food industries. The action of this compound is based on inhibition of tyrosinase activity, which helps to protect
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Published 14 Oct 2024

Transition-metal-free synthesis of arylboronates via thermal generation of aryl radicals from triarylbismuthines in air

  • Yuki Yamamoto,
  • Yuki Konakazawa,
  • Kohsuke Fujiwara and
  • Akiya Ogawa

Beilstein J. Org. Chem. 2024, 20, 2577–2584, doi:10.3762/bjoc.20.216

Graphical Abstract
  • 2 in BTF (0.4 mL) at 80 °C in air successfully afforded phenylboronic acid pinacol ester 3a in 68% yield (Table 1, entry 1). In the presence of NaOMe as a base, the reaction did not proceed (Table 1, entry 2). Increasing or decreasing the amount of diboron 2 did not improve the yield of 3a (Table 1
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Published 11 Oct 2024

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

  • Nian Li,
  • Ruzal Sitdikov,
  • Ajit Prabhakar Kale,
  • Joost Steverlynck,
  • Bo Li and
  • Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

Graphical Abstract
  • , several structurally diverse aromatic acetals have been synthesized. Dehydroabietic and norcholanoic acid derivatives have been effectively modified using the developed protocol. The reaction is reported to involve the oxidation of the benzene core, followed by electron transfer to the radical cation, and
  • . Subsequently, the generated intermediate 29 is oxidized at the anode, then attacked by the acid to obtain the final product (Scheme 10). C–H bond sulfur functionalization: The direct formation of the CS bond is an attractive way to prepare aryl sulfides. From this perspective, Wu and coworkers developed a
  • then attacked by the nucleophilic amidosulfinate, which also functions as an electrolyte. The amidosulfinate is generated through the formation of a Lewis acid–base adduct. A subsequent oxidation step, accompanied by deprotonation, yields the sulfonamide product. SO2 captures the excess electrons via
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Review
Published 09 Oct 2024

Machine learning-guided strategies for reaction conditions design and optimization

  • Lung-Yi Chen and
  • Yi-Pei Li

Beilstein J. Org. Chem. 2024, 20, 2476–2492, doi:10.3762/bjoc.20.212

Graphical Abstract
  • acid–base salts, and continuous variables, such as temperature, pressure, substrate concentration, and residence time. Regression prediction models are then built for these reaction parameters and target objectives by collecting experimental data and conducting statistical analysis. Many reaction
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Published 04 Oct 2024
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