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Search for "temperature" in Full Text gives 3009 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Approaches to stereoselective 1,1'-glycosylation

  • Daniele Zucchetta and
  • Alla Zamyatina

Beilstein J. Org. Chem. 2025, 21, 1700–1718, doi:10.3762/bjoc.21.133

Graphical Abstract
  • diminish the reactivity of N-Troc-protected GlcN-derived donors [72]. Indeed, the presence of an electron-withdrawing group at position 3 of the GlcN-derived donor 70 merely required an elevated reaction temperature (0 °C), in contrast to the conditions used for the 3-O-Nap-protected GalN-based donor 68
  • (reaction temperature −60 °C). Permanent ether-type protecting groups, such as benzyl, or those that require harsh acidic or basic conditions for removal, are often incompatible with the labile functional groups present in complex biomolecules derived from synthetic nonreducing disaccharides. To address
  • reduced reaction temperatures (−20 to −60 °C), N-phenyl trifluoroacetimidate (PTFA) donors are sufficiently stable to be used in glycosylation reactions at 0 °C or ambient temperature, while remaining reactive enough to glycosylate conformationally hindered nucleophiles in the presence of catalytic TMSOTf
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Published 27 Aug 2025

Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade

  • Feng Zhou,
  • Chuansong Duanmu,
  • Yanxing Li,
  • Jin Li,
  • Haiqing Xu,
  • Pan Wang and
  • Kai Zhu

Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132

Graphical Abstract
  • /selectivity through optimized parameters (microwave energy, temperature, feed composition) [11]. Recent years have witnessed growing adoption of the continuous-flow technology in nitration processes across laboratory and industrial scales, driven by the reaction's classification as a highly hazardous chemical
  • reactors. For intensely exothermic nitration reactions with rapid kinetics, this technology enables uniform mixing, efficient heat removal, and precise control of critical parameters including reaction temperature and reactant stoichiometry. Crucially, continuous operation permits scalable production of
  • generated during the dilution process. While many nitration processes usually exhibit rapid kinetics, specific transformations like partial dinitration reactions demonstrate notably slower reaction rates, substantially compromising process throughput. Although thermal activation via temperature elevation
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Published 26 Aug 2025

Structural analysis of stereoselective galactose pyruvylation toward the synthesis of bacterial capsular polysaccharides

  • Tsun-Yi Chiang,
  • Mei-Huei Lin,
  • Chun-Wei Chang,
  • Jinq-Chyi Lee and
  • Cheng-Chung Wang

Beilstein J. Org. Chem. 2025, 21, 1671–1677, doi:10.3762/bjoc.21.131

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  • function. Careful manipulation of reaction conditions such as solvent and temperature is necessary to achieve sufficient diastereomeric purity in pyruvate modification. This research contributes to the development in the field of polysaccharide synthesis and draws upon established methodologies, reflecting
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Published 21 Aug 2025

Influence of the cation in hypophosphite-mediated catalyst-free reductive amination

  • Natalia Lebedeva,
  • Fedor Kliuev,
  • Olesya Zvereva,
  • Klim Biriukov,
  • Evgeniya Podyacheva,
  • Maria Godovikova,
  • Oleg I. Afanasyev and
  • Denis Chusov

Beilstein J. Org. Chem. 2025, 21, 1661–1670, doi:10.3762/bjoc.21.130

Graphical Abstract
  • the further study. Using the optimal K2CO3/H3PO2 ratio 0.125/0.5, it was found that 78% yield of the model amine could be reached at lower temperature (110 °C) under prolonged reaction time (Scheme 2). The water content in the system had a crucial influence on the reaction outcome: an excess of the
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Published 20 Aug 2025

Synthesis of optically active folded cyclic dimers and trimers

  • Ena Kumamoto,
  • Kana Ogawa,
  • Kazunori Okamoto and
  • Yasuhiro Morisaki

Beilstein J. Org. Chem. 2025, 21, 1603–1612, doi:10.3762/bjoc.21.124

Graphical Abstract
  • samples were analyzed in CHCl3 at room temperature. Photoluminescence (PL) spectra were recorded on a JASCO FP-8500 spectrofluorometer, and samples were analyzed in CHCl3 at room temperature. Absolute PL quantum efficiency was calculated on a JASCO FP-8500 with an ILF-835 integrating sphere. The PL
  • with CHCl3 as a solvent at room temperature. Circularly polarized luminescence (CPL) spectra were recorded on a JASCO CPL-300 with CHCl3 as a solvent at room temperature. Materials Commercially available compounds used without purification are as follows: Pd2(dba)3, SPhos (2-dicyclohexylphosphino-2',6
  • mmol), Pd2(dba)3 (6.1 mg, 0.0067 mmol), SPhos (5.6 mg, 0.014 mmol), CuI (1.8 mg, 0.0095 mmol), toluene (40 mL) and Et3N (40 mL) was placed in a round-bottom flask equipped with a magnetic stirring bar. After degassing the reaction mixture several times, the mixture was heated at reflux temperature for
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Published 11 Aug 2025

3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles

  • Julia I. Pavlenko,
  • Pavel A. Sakharov,
  • Anastasiya V. Agafonova,
  • Derenik A. Isadzhanyan,
  • Alexander F. Khlebnikov and
  • Mikhail S. Novikov

Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123

Graphical Abstract
  • reaction. The highest yield of 3a (85%) was achieved by treating 1 with 3.2 equiv of the azirine in MeOH at 100 °С with 50 mol % of Ni(hfacac)2 (Table 1, entry 13). Lowering the temperature and the catalyst loading resulted in a slight deterioration in the yield and a significant slowing of the reaction
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Published 11 Aug 2025

Chemical synthesis of glycan motifs from the antitumor agent PI-88 through an orthogonal one-pot glycosylation strategy

  • Shaokang Yang,
  • Xingchun Sun,
  • Hanyingzi Fan and
  • Guozhi Xiao

Beilstein J. Org. Chem. 2025, 21, 1587–1594, doi:10.3762/bjoc.21.122

Graphical Abstract
  • in mannosyl PVB 8 (1.0 equiv) in the presence of TMSOTf as catalyst proceeded smoothly at 0 °C to room temperature, affording the α-Man-(1→3)-Man PVB disaccharide. The further coupling of the above PVB disaccharide with the poorly reactive 2-OH in mannoside 9 (0.9 equiv) under activation with NIS and
  • TMSOTf at 0 °C to room temperature, successfully furnished the desired α-Man-(1→3)-α-Man-(1→3)-α-Man trisaccharide 10 in 87% yield in a one pot manner. Removal of TBDPS group in 10 with 70% HF·pyridine and subsequent phosphitylation of the resulting free alcohol with phosphoramidite 11 provided the
  • all Bz groups with 1 M NaOH (dioxane/MeOH/H2O, room temperature). The monophosphorylated trisaccharide 1 was obtained in 60% overall yield over two steps from 12 after purification over a SephadexTM LH-20 column. It was noted that the switch of deprotection sequences (first Bz groups, second Bn and
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Published 06 Aug 2025

Thermodynamic equilibrium between locally excited and charge transfer states in perylene–phenothiazine dyads

  • Issei Fukunaga,
  • Shunsuke Kobashi,
  • Yuki Nagai,
  • Hiroki Horita,
  • Hiromitsu Maeda and
  • Yoichi Kobayashi

Beilstein J. Org. Chem. 2025, 21, 1577–1586, doi:10.3762/bjoc.21.121

Graphical Abstract
  • -carborane exhibit such behavior, where LE and CT states dynamically interconvert depending on solvent polarity and temperature [10][11][12]. When the interconversion is faster than radiative decay, the two states can reach thermodynamic equilibrium, and their relative populations are determined by the
  • the degree of electronic interaction between the donor PTZ and acceptor Pe moieties, as indicated by the decreased overlap between HOMO and LUMO. UV–vis absorption spectra of the Pe–PTZ derivatives were recorded in benzene at room temperature (Figure 3a). All compounds exhibited characteristic
  • phenothiazine derivative, 12-phenyl-12H-benzo[a]phenothiazine, in toluene at room temperature has been estimated to be 28 ps (with an additional minor 0.7 ps component attributed to small-scale structural changes) [17]. It is also noted that the relaxation dynamics depend on the molecular structure and the
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Published 05 Aug 2025

pH-Controlled isomerization kinetics of ortho-disubstituted benzamidines: E/Z isomerism and axial chirality

  • Ryota Kimura,
  • Satoshi Ichikawa and
  • Akira Katsuyama

Beilstein J. Org. Chem. 2025, 21, 1568–1576, doi:10.3762/bjoc.21.120

Graphical Abstract
  • bond rotation was investigated by variable temperature nuclear magnetic resonance (VT-NMR) spectra (Figure 3) in DMSO-d6 [27]. In the case of the molecular form of amidine 1 (Figure 3a), the signals corresponding to the two methyl groups resulting from the amidine E/Z isomerism were observed separately
  • at 313 K (1.17 and 0.95 ppm), and they gradually fused as the temperature increased. The activation energy of E/Z isomerization was calculated to be 77 kJ·mol−1 from the observed coalescence temperature (Tc = 378 K). On the other hand, the two methyl signals of amidine 1 trifluoroacetate salt were
  • . Notably, at pH 9.2, racemization proceeded minimally, even under high temperature conditions. Furthermore, it was confirmed that racemization requires a higher pH where a higher proportion of the amidine exists in its molecular form. This result was consistent with our DFT calculations, which showed that
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Published 04 Aug 2025

Synthesis of an aza[5]helicene-incorporated macrocyclic heteroarene via oxidation of an o-phenylene-pyrrole-thiophene icosamer

  • Yusuke Matsuo,
  • Aoi Nakagawa,
  • Shu Seki and
  • Takayuki Tanaka

Beilstein J. Org. Chem. 2025, 21, 1561–1567, doi:10.3762/bjoc.21.119

Graphical Abstract
  • acyclic heteroaromatics [26][27]. Thus, to a solution of 4 in CH2Cl2 was added 15 equivalents of PIFA at −78 °C and stirred for 3 h. The mixture was then allowed to warm to room temperature to give a dark solution. The system was worked-up with NaBH4/MeOH for 10 minutes followed by extraction with CH2Cl2
  • and evaporation of the solvent to afford a crude product, which was recrystallized from THF to give 5 in 58% yield. Due to its poor solubility in common organic solvents, the 1H NMR spectrum could only be recorded in DMSO. At room temperature, the 1H NMR spectrum in DMSO-d6 exhibited broad signals in
  • at 399 nm (Figure 5b). A broad emission was observed at 528 nm, resulting in a relatively large Stokes shift of 6100 cm−1, which can be attributed to the structural relaxation in the excited state, as inferred by the observed broad 1H NMR spectrum at room temperature. Due to the thermal energy loss
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Published 31 Jul 2025

Facile synthesis of hydantoin/1,2,4-oxadiazoline spiro-compounds via 1,3-dipolar cycloaddition of nitrile oxides to 5-iminohydantoins

  • Juliana V. Petrova,
  • Varvara T. Tkachenko,
  • Victor A. Tafeenko,
  • Anna S. Pestretsova,
  • Vadim S. Pokrovsky,
  • Maxim E. Kukushkin and
  • Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 1552–1560, doi:10.3762/bjoc.21.118

Graphical Abstract
  • dipolarophiles into the 32CA, it is reasonable to utilize conditions that minimize the side reactions of the dipole. This could include lowering the temperature [32] and slowly adding a base [33]. In this work we have tested two alternative techniques for the dipolar cycloaddition. In the first method, a
  • ]. The most dramatic discrepancy in spiro-compound yields was observed during the reaction with this nitrile oxide, suggesting that classical conditions (low temperature and inert atmosphere) may prove more fruitful in preventing the degradation of the dipole. The influence of the concentration of the
  • decomposing even at room temperature. Taking these into account, we have synthesized compound 5c using an alternative route starting from the chloro oxime 4a and 5-iminothiohydantoin 2j (Scheme 4), obtained similarly to other dipolarophiles [22]. The total yield of the product 5c in this case turned out to be
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Published 31 Jul 2025

Azide–alkyne cycloaddition (click) reaction in biomass-derived solvent CyreneTM under one-pot conditions

  • Zoltán Medgyesi and
  • László T. Mika

Beilstein J. Org. Chem. 2025, 21, 1544–1551, doi:10.3762/bjoc.21.117

Graphical Abstract
  • capillary column (15 m × 0.25 mm × 0.25 µm) using H2 as a carrier gas. For the analysis, 10 μL of the reaction mixture was dissolved in 1 mL of ethyl acetate, followed by adding 10 μL toluene as the internal standard. Heating profile of GC–FID analysis: The initial temperature was 100 °C and was hold for
  • 0.5 min. Heating rate: 40 °C/min up to the final temperature of 270 °C. The final temperature was held for 4.25 min. The water content of CyreneTM was measured on a Methrom 684 KF Coulometer at Balint Analitika Ltd, Budapest, Hungary. CyreneTM was purchased from Sigma-Aldrich Kft. Budapest, Hungary
  • , and 0.01 mmol CuI, were dissolved in 2.5 mL CyreneTM. The reaction mixture was stirred overnight at a given temperature. After the reaction, 20 mL of cold distilled water was added, followed by intensive stirring. The solid product was filtered, washed with distilled water (3 × 5 mL), and dried until
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Published 30 Jul 2025

General method for the synthesis of enaminones via photocatalysis

  • Paula Pérez-Ramos,
  • Raquel G. Soengas and
  • Humberto Rodríguez-Solla

Beilstein J. Org. Chem. 2025, 21, 1535–1543, doi:10.3762/bjoc.21.116

Graphical Abstract
  • by DME, DMSO or acetone diminished the product yields (Table 1, entries 7–9). The reactivity of acridinium PC1 was superior to that of other photocatalysts, including 4-CzlPN (PC2) and [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 (PC3) (Table 1, entries 10 and 11). Attempts to increase the temperature of the process
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Published 29 Jul 2025

Azobenzene protonation as a tool for temperature sensing

  • Antti Siiskonen,
  • Sami Vesamäki and
  • Arri Priimagi

Beilstein J. Org. Chem. 2025, 21, 1528–1534, doi:10.3762/bjoc.21.115

Graphical Abstract
  • changes in their absorption and photochemical properties. While azobenzene protonation has been recently used as a tool in photoswitching studies, the factors influencing protonation itself have received little attention. Here, we report a strong temperature dependence of azobenzene protonation in 1,2
  • -dichloroethane and highlight its potential for temperature sensing applications. Density functional theory calculations were performed to support our findings and to investigate the mechanisms of azobenzene–acid interactions, aiming to guide the design of azobenzene-based temperature sensors in future research
  • . Keywords: azobenzene; protonation; sensing; spectral changes; temperature; Introduction Molecular switches are molecules that can reversibly shift between distinct (meta)stable states in response to external stimuli such as light, pH changes, or electric fields [1]. Over the past decades, they have
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Published 28 Jul 2025

Calcium waste as a catalyst in the transesterification for demanding esters: scalability perspective

  • Anton N. Potorochenko and
  • Konstantin S. Rodygin

Beilstein J. Org. Chem. 2025, 21, 1520–1527, doi:10.3762/bjoc.21.114

Graphical Abstract
  • % yields, respectively. The transesterification of soybean oil (1a) with methanol (2a) was carried out as a gram-scale batch reaction using 21 g of soybean oil, 210 mg of catalyst (1 wt %), and 11.7 mL of methanol (Scheme 3). The temperature and reaction time conditions used were the same as in the
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Published 28 Jul 2025

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

  • Grzegorz Mlostoń,
  • Małgorzata Celeda,
  • Marcin Palusiak,
  • Heinz Heimgartner,
  • Marta Denel-Bobrowska and
  • Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

Graphical Abstract
  • slightly higher temperature (60 °C). In both cases, evolution of nitrogen was completed after ca. 3 h and pure thiiranes 8a and 8b were isolated as sole products in 62%, and 58% yield, respectively (Scheme 4). Thus, their formation clearly evidenced formation of the respective thiocarbonyl S-methanides 1c
  • stable 9 into the more stable 10 was observed in some cases (derived from 1c) in the CDCl3 solution at room temperature. Therefore, it seems likely that the first step of the reaction is the N–H insertion process. The compositions of the obtained crude mixtures suggest that the final addition step
  • the sterically most hindered dispiro-cyclohexyl-substituted thiocarbonyl S-methanide 2d. Notably, in some cases spontaneous isomerization of the generally less stable thioaminals 9 in CDCl3 solution at room temperature was also observed. It seems likely that this isomerization follows an
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Published 23 Jul 2025

Highly distinguishable isomeric states of a tripodal arylazopyrazole derivative on graphite through electron/hole-induced switching at ambient conditions

  • Himani Malik,
  • Sudha Devi,
  • Debapriya Gupta,
  • Ankit Kumar Gaur,
  • Sugumar Venkataramani and
  • Thiruvancheril G. Gopakumar

Beilstein J. Org. Chem. 2025, 21, 1496–1507, doi:10.3762/bjoc.21.112

Graphical Abstract
  • isomer of azobenzene (AB) is a few days. Arylazopyrazole-based molecular switches are one of the profoundly explored systems in recent times due to their superior bidirectional photoswitching and long half-life (over a thousand days at room temperature) of Z isomers. Herein, we utilize an efficient solid
  • experimental conditions. The choice of molecules that can be studied under ultra-high vacuum (UHV) is limited due to the requirement of their thermal stability and UHV compatible sublimation temperature. Therefore, the solution-based preparation method and solid-state measurements at ambient conditions hold
  • barrier and the long lifetime of the non-equilibrium states are at the origin of their remarkable stability at room temperature. The remarkable stability of the states at ambient conditions provides an opportunity to use a single FNAAP molecule as an 8-bit operation. We propose to switch the molecule
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Published 22 Jul 2025

Photoredox-catalyzed arylation of isonitriles by diaryliodonium salts towards benzamides

  • Nadezhda M. Metalnikova,
  • Nikita S. Antonkin,
  • Tuan K. Nguyen,
  • Natalia S. Soldatova,
  • Alexander V. Nyuchev,
  • Mikhail A. Kinzhalov and
  • Pavel S. Postnikov

Beilstein J. Org. Chem. 2025, 21, 1480–1488, doi:10.3762/bjoc.21.110

Graphical Abstract
  • . Finally, control experiments without irradiation gave only traces of the benzamide 2aa showing no activation by the Ru complex at room temperature (Table 1, entry 24). An experiment conducted under an air atmosphere yielded only 9% of 2aa (Table 1, entry 25) indicating that the presence of atmospheric
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Published 21 Jul 2025

Microwave-enhanced additive-free C–H amination of benzoxazoles catalysed by supported copper

  • Andrei Paraschiv,
  • Valentina Maruzzo,
  • Filippo Pettazzi,
  • Stefano Magliocco,
  • Paolo Inaudi,
  • Daria Brambilla,
  • Gloria Berlier,
  • Giancarlo Cravotto and
  • Katia Martina

Beilstein J. Org. Chem. 2025, 21, 1462–1476, doi:10.3762/bjoc.21.108

Graphical Abstract
  • , that still required high temperatures, but the excess of amine (2 equiv) was lowered and only a catalytic amount of acid was utilised. Similar acidic protocols were subsequently developed by Li et al. [46], in which benzoxazoles were reacted with secondary amines and amides, with higher temperature
  • being applied when reacting amides to achieve their decarbonylation. In 2014, Cao et al. [47] reported the amination of benzoxazole with a secondary amine either in air or an O2 atmosphere, lowering the catalyst amount and the reaction temperature. In 2020, a study by De Vos and co-workers [48] focused
  • to 6 hours, with a catalyst loading of 20 mol %, resulted in complete conversion and high selectivity, comparable to the results obtained from an overnight reaction. Notably, decreasing the reaction temperature to 60 °C still yielded excellent results with both catalysts after an overnight reaction
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Published 15 Jul 2025

Wittig reaction of cyclobisbiphenylenecarbonyl

  • Taito Moribe,
  • Junichiro Hirano,
  • Hideaki Takano,
  • Hiroshi Shinokubo and
  • Norihito Fukui

Beilstein J. Org. Chem. 2025, 21, 1454–1461, doi:10.3762/bjoc.21.107

Graphical Abstract
  • internally functionalized DBC derivatives [22]. The dihedral angle between the mean planes of the two terminal benzene units is 83°, which is comparable to those of other derivatives. Next, products 3 and 5 were analyzed by variable temperature (VT) 1H NMR spectroscopy. The 1H NMR spectrum of bis-olefin 5 in
  • CD2Cl2 at 298 K shows a symmetric pattern, in which the signal due to the methylene protons appears as one singlet (Figure 3). The decrease of temperature to 243 K resulted in the broadening of the 1H NMR spectrum and the appearance of two sets of signals which sharpened upon further decrease of the
  • temperature. These are attributable to the mixture of conformers with the figure-eight conformation as minor and the bathtub conformation as major conformer with a ratio of ca. 1:7. The obtained temperature-dependent 1H NMR data were subjected to the van't Hoff plot, affording an enthalpy ΔH and an entropy ΔS
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Published 14 Jul 2025

Advances in nitrogen-containing helicenes: synthesis, chiroptical properties, and optoelectronic applications

  • Meng Qiu,
  • Jing Du,
  • Nai-Te Yao,
  • Xin-Yue Wang and
  • Han-Yuan Gong

Beilstein J. Org. Chem. 2025, 21, 1422–1453, doi:10.3762/bjoc.21.106

Graphical Abstract
  • core [17]. Compared to 4a, compound 4b exhibits bathochromic shifts of 12 nm in absorption and 45 nm in emission, as well as a higher ΦF (0.75 vs 0.68). Both isomers display TADF at room temperature and phosphorescence at 77 K. Notably, 4a demonstrates a long-lived red afterglow persisting for up to 30
  • showed more intense phosphorescence and an extended emission lifetime in dilute solution. Notably, it demonstrated room-temperature dual-emission CPL originating from both prompt fluorescence and long-lived phosphorescence, a rare feature in helicene systems. In a subsequent study, the same group
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Published 11 Jul 2025

Tautomerism and switching in 7-hydroxy-8-(azophenyl)quinoline and similar compounds

  • Lidia Zaharieva,
  • Vera Deneva,
  • Fadhil S. Kamounah,
  • Nikolay Vassilev,
  • Ivan Angelov,
  • Michael Pittelkow and
  • Liudmil Antonov

Beilstein J. Org. Chem. 2025, 21, 1404–1421, doi:10.3762/bjoc.21.105

Graphical Abstract
  • influenced by the structural variations and the environment (temperature, solvent properties, acidity and presence of other molecules). The E/Z isomerization of the azodyes, caused by light irradiation [12][13][14] or electrochemically [15][16], has paved the way for the development of innovative materials
  • number of industrially used azo dyes [1][3] and therefore its tautomerism is studied in details. The existing experimental data for low polar solvents (cyclohexane and tetrachloromethane) indicate a ΔG value of around 0.4 kcal/mol [53] at room temperature, which gives a prevalence of the E-tautomer (a
  • makes possible to analyze the tautomerism in 1 as a function of (E+KE) and KK. The NMR spectra of 1 in acetonitrile-d3 are in agreement with the above analysis of tautomeric equilibration based on theoretical calculations and UV spectra. At room temperature the proton signals are very broad and
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Published 10 Jul 2025

Reactions of acryl thioamides with iminoiodinanes as a one-step synthesis of N-sulfonyl-2,3-dihydro-1,2-thiazoles

  • Vladimir G. Ilkin,
  • Pavel S. Silaichev,
  • Valeriy O. Filimonov,
  • Tetyana V. Beryozkina,
  • Margarita D. Likhacheva,
  • Pavel A. Slepukhin,
  • Wim Dehaen and
  • Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2025, 21, 1397–1403, doi:10.3762/bjoc.21.104

Graphical Abstract
  • expectations were not fulfilled. The exception is the data from entry 7 (Table 1), where the yield of compound 3aa was 78%. Thus, the conditions described in entry 7 (absence of a catalyst, use of 1.5 equiv of PhINTs 2a and dichloromethane (DCM) as a solvent at room temperature for 10 min) are optimal and were
  • iodonium salts. The search for optimal conditions for the process has been carried out. The optimized reaction found to proceed in the absence of metal catalysts, using 1.5 equiv of the iodonium salt at room temperature in DCM. Using the optimized procedure, a library of 31 novel 2,3-dihydro-1,2-thiazoles
  • thioamides 1h,i,k,n,o,s,t,v,w,y,z (general procedure). A mixture of the corresponding thioacetamide (1.0 equiv), aldehyde (1.1–4.0 equiv) and DBU (0.1 equiv or 1.0 equiv for 1h,o) in ethanol was stirred for 2–23 h at room temperature. For thioamide 1i, the reaction time was 96 h at 80 °C. The formed
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Published 10 Jul 2025

N-Salicyl-amino acid derivatives with antiparasitic activity from Pseudomonas sp. UIAU-6B

  • Joy E. Rajakulendran,
  • Emmanuel Tope Oluwabusola,
  • Michela Cerone,
  • Terry K. Smith,
  • Olusoji O. Adebisi,
  • Adefolalu Adedotun,
  • Gagan Preet,
  • Sylvia Soldatou,
  • Hai Deng,
  • Rainer Ebel and
  • Marcel Jaspars

Beilstein J. Org. Chem. 2025, 21, 1388–1396, doi:10.3762/bjoc.21.103

Graphical Abstract
  • (3 and 4) isolated alongside three known compounds, pseudomonine (5), pseudomonin B (6) and salicylic acid (7) [15] from the Pseudomonas sp. UIAU-6B strain by altering the fermentation conditions using an open system shaker at room temperature [16][17][18]. Results and Discussion The bacterial strain
  • Pseudomonas sp. UIAU-6B was investigated by varying the temperature of the culture to elicit production of secondary metabolites after our previous work on the strain [15]. A small-scale culture of the strain (50 mL of SGG medium) shaken at 160 rpm in an open system shaker at room temperature yielded 0.008 g
  • previously isolated pseudomonine [15]. This resulted in the decision to upscale the bacterial strain at room temperature in an open orbital shaker. The large crude extract (7.5 g) was subjected to Kupchan solvent partitioning followed by medium pressure liquid chromatography (MPLC) and subsequently
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Published 04 Jul 2025

High-pressure activation for the solvent- and catalyst-free syntheses of heterocycles, pharmaceuticals and esters

  • Kelsey Plasse,
  • Valerie Wright,
  • Guoshu Xie,
  • R. Bernadett Vlocskó,
  • Alexander Lazarev and
  • Béla Török

Beilstein J. Org. Chem. 2025, 21, 1374–1387, doi:10.3762/bjoc.21.102

Graphical Abstract
  • generation. Using water as pressure transmitting fluid, the reaction vessel is immersed in water minimizing fire hazard during the reactions. Finally, most procedures can be carried out at ambient temperature, improving safety and energy efficiency. Energy efficiency is also supported by the nature of the
  • -phenylenediamine and acetone was selected as a model reaction. The optimization of the reaction conditions is summarized in Table 1. All reactions were carried out at room temperature without involving any catalyst or additional solvent. While o-phenylenediamine is solid, it dissolves well in the reactant acetone
  • subjected to those conditions to provide a representative scope of the reactions and the results are summarized in Scheme 2. For comparison, the yields obtained under ambient pressure (1 bar) are provided in parentheses. The data show that the reactions readily occur at room temperature providing good
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Published 02 Jul 2025
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