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Search for "heating" in Full Text gives 1025 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Asymmetric synthesis of fluorinated derivatives of aromatic and γ-branched amino acids via a chiral Ni(II) complex

  • Maurizio Iannuzzi,
  • Thomas Hohmann,
  • Michael Dyrks,
  • Kilian Haoues,
  • Katarzyna Salamon-Krokosz and
  • Beate Koksch

Beilstein J. Org. Chem. 2025, 21, 659–669, doi:10.3762/bjoc.21.52

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  • Schlenk vessels at a Schlenk unit/oil pump vacuum under nitrogen atmosphere. The stated reaction temperatures are the respective values of the silicone oil heating bath. All reactions were stirred with an electric magnetic stirrer. 1H, 13C, and 19F NMR spectra were measured at room temperature with a JEOL
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Published 21 Mar 2025

Sequential two-step, one-pot microwave-assisted Urech synthesis of 5-monosubstituted hydantoins from L-amino acids in water

  • Wei-Jin Chang,
  • Sook Yee Liew,
  • Thomas Kurz and
  • Siow-Ping Tan

Beilstein J. Org. Chem. 2025, 21, 596–600, doi:10.3762/bjoc.21.46

Graphical Abstract
  • advantages over conventional heating, such as enhanced reaction rates and yields [17]. Microwave irradiation is also aligned with our group’s sustainability goals of adhering to the principles of green chemistry [18]. Following our previous works in the synthesis and evaluation of biologically active
  • were first verified using different equivalents of KOCN at different temperatures in water under microwave heating conditions (Scheme 1, Table 1), and 5.0 equiv of KOCN and microwave irradiation at 80 °C produced the best yield for H1a (Table 1, entry 2). Inspired by the simplicity of the procedure, a
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Published 14 Mar 2025

Formaldehyde surrogates in multicomponent reactions

  • Cecilia I. Attorresi,
  • Javier A. Ramírez and
  • Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

Graphical Abstract
  • colorless crystals from the reaction between Et3N and CH2Cl2 at 100 °C in DMF. Subsequently, the corresponding α-aminophosphonate 35a was obtained by heating 36a with an equal amount of diethyl phosphite (Scheme 28b). Furthermore, when the reaction was carried out with CD2Cl2, the corresponding deuterated
  • formaldehyde and ammonia in situ by heating [83]. Under these conditions, the water present in hydrated HMTA is sufficient for this hydrothermal decomposition to occur. On the other hand, an excess of ammonia must be added to the reaction mixture to shift the equilibrium towards the imine. Using this procedure
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Published 13 Mar 2025

Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene

  • Long K. San,
  • Sebastian Balser,
  • Brian J. Reeves,
  • Tyler T. Clikeman,
  • Yu-Sheng Chen,
  • Steven H. Strauss and
  • Olga V. Boltalina

Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39

Graphical Abstract
  • reactions) Dry Mg turnings (excess) were added to an oven-dried 100 mL Schlenk flask and mechanically activated via stirring and heating. After 1 h, dry THF (20 mL) and 9,10-ANTH(Br)2 (84 mg, 0.25 mmol) were added. Several activation methods were tried (ultra sonic bath, careful heating, addition of I2
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Published 07 Mar 2025

Synthesis of electrophile-tethered preQ1 analogs for covalent attachment to preQ1 RNA

  • Laurin Flemmich and
  • Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 483–489, doi:10.3762/bjoc.21.35

Graphical Abstract
  • was observed, and the alcohol intermediate was isolated in pure form. In both cases, quantitative bromination was achieved by heating the compounds in concentrated aqueous hydrobromic acid, which after evaporation afforded the pure compounds 4b–d. To generate iodide 4e, alcohol 11 was isolated and
  • 3b in almost quantitative yield. The bis(3-bromopropyl)-modified ligand 3c was generated by heating preQ1 together with bis(3-hydroxypropyl)amine. It is noteworthy that the amine exchange reaction is thought to proceed via a purine methide intermediate [11]. Subsequent treatment of the diol with
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Published 04 Mar 2025

Photomechanochemistry: harnessing mechanical forces to enhance photochemical reactions

  • Francesco Mele,
  • Ana M. Constantin,
  • Andrea Porcheddu,
  • Raimondo Maggi,
  • Giovanni Maestri,
  • Nicola Della Ca’ and
  • Luca Capaldo

Beilstein J. Org. Chem. 2025, 21, 458–472, doi:10.3762/bjoc.21.33

Graphical Abstract
  • resulted in 40% yield. Alternating grinding and irradiation, the authors managed to obtain quantitative conversion of 2.1 to 2.3. Overall, in this work, mechanochemistry worked akin to agitation provided by stirring or heating in solution. In fact, 1H NMR spectroscopy, XRD and DFT analyses showed that
  • Na2CO3 was ground in a mortar at room temperature for 3–5 min. Second, the reaction mixture was transferred into a quartz tube, heated to 50 °C (heating mantle) for 18 h, while being irradiated with blue LEDs under air-equilibrated conditions. In these conditions, product 3.3 was isolated in excellent
  • starting materials. The authors also noted that the reaction proceeds in the dark upon vigorous heating (120 °C). The reaction could be performed on a gram scale as well, leading to the formation of 3.3 in 92% yield. The examples described above demonstrate that manual grinding offers simplicity and low
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Published 03 Mar 2025

Synthesis, structure, ionochromic and cytotoxic properties of new 2-(indolin-2-yl)-1,3-tropolones

  • Yurii A. Sayapin,
  • Eugeny A. Gusakov,
  • Inna O. Tupaeva,
  • Alexander D. Dubonosov,
  • Igor V. Dorogan,
  • Valery V. Tkachev,
  • Anna S. Goncharova,
  • Gennady V. Shilov,
  • Natalia S. Kuznetsova,
  • Svetlana Y. Filippova,
  • Tatyana A. Krasnikova,
  • Yanis A. Boumber,
  • Alexey Y. Maksimov,
  • Sergey M. Aldoshin and
  • Vladimir I. Minkin

Beilstein J. Org. Chem. 2025, 21, 358–368, doi:10.3762/bjoc.21.26

Graphical Abstract
  • the formation of trichlorosubstituted 1,3-tropolones 7a,b as the main reaction products (Scheme 2). Heating 2a,b in acetic acid with a two-fold excess of o-chloranil (3) (method B) is accompanied by the formation of tetrachlorosubstituted 1,3-tropolones 8a,b (Scheme 2 and Supporting Information File 1
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Published 17 Feb 2025

Synthesis, characterization, antimicrobial, cytotoxic and carbonic anhydrase inhibition activities of multifunctional pyrazolo-1,2-benzothiazine acetamides

  • Ayesha Saeed,
  • Shahana Ehsan,
  • Muhammad Zia-ur-Rehman,
  • Erin M. Marshall,
  • Sandra Loesgen,
  • Abdus Saleem,
  • Simone Giovannuzzi and
  • Claudiu T. Supuran

Beilstein J. Org. Chem. 2025, 21, 348–357, doi:10.3762/bjoc.21.25

Graphical Abstract
  • Dried acetonitrile (10 mL) was used to prepare a solution of compound 5 (251 mg, 1.0 mmol) followed by addition of anhydrous K2CO3 (173 mg, 1.25 mmol) under continuous stirring and heating. After 30 minutes, the solution of the respective 2-chloro-N-aryl/benzyl/cyclohexylacetamide 6a–h (1 mmol) in dry
  • -benzothiazine-N-aryl/benzyl/cyclohexylacetamides 7i–n Dried acetonitrile (10 mL) was used to prepare a solution of compound 5 (1.0 mmol, 251 mg) followed by the addition of anhydrous K2CO3 (297 mg, 2.15 mmol) under continuous stirring and heating. After 30 minutes, the solution of respective 2-chloro-N-aryl
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Published 12 Feb 2025

Three-component reactions of conjugated dienes, CH acids and formaldehyde under diffusion mixing conditions

  • Dmitry E. Shybanov,
  • Maxim E. Kukushkin,
  • Eugene V. Babaev,
  • Nikolai V. Zyk and
  • Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 262–269, doi:10.3762/bjoc.21.18

Graphical Abstract
  • [4][5][6] and polymerization processes of unstable methylidene adducts [7][8][9], instead of the desired formation of a monocrotonic product. Therefore, heating [6][10][11][12][13][14] or Lewis acid activation [15][16][17][18] have often been used in the literature for successful multicomponent
  • formaldehyde (generated from paraformaldehyde upon heating), an adduct of a methylidene derivative of a CH acid dienophile was detected in some cases only in reference [15] (when carrying out the reaction in a sealed tube in the presence of copper(II) acetate). However, in most reactions only the hetero-Diels
  • ) are worth mentioning since according to the literature, unstable crotonic condensation adducts are usually generated upon heating [6][10][11][12][13][15], in acidic medium [15][23] or using oxidizing agents [24][25]. Three-component reactions under diffusion mixing conditions Under optimized
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Published 04 Feb 2025

Heteroannulations of cyanoacetamide-based MCR scaffolds utilizing formamide

  • Marios Zingiridis,
  • Danae Papachristodoulou,
  • Despoina Menegaki,
  • Konstantinos G. Froudas and
  • Constantinos G. Neochoritis

Beilstein J. Org. Chem. 2025, 21, 217–225, doi:10.3762/bjoc.21.13

Graphical Abstract
  • fashion, substituted indolopyrimidone derivatives 7a–e were obtained within 3 h in 31–90% total yield (2 steps) upon heating with formamide (Scheme 5). Next, we characterized certain physicochemical properties of the newly synthesized compounds. The absorbance and emission spectra of 5–7 were obtained
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Published 24 Jan 2025

Recent advances in organocatalytic atroposelective reactions

  • Henrich Szabados and
  • Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

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Published 09 Jan 2025

Hot shape transformation: the role of PSar dehydration in stomatocyte morphogenesis

  • Remi Peters,
  • Levy A. Charleston,
  • Karinan van Eck,
  • Teun van Berlo and
  • Daniela A. Wilson

Beilstein J. Org. Chem. 2025, 21, 47–54, doi:10.3762/bjoc.21.5

Graphical Abstract
  • demonstrated that polysarcosine-based self-assemblies could undergo shape transformation via dehydration induced by heating [16]. This dehydration of the polysarcosine caused in their system a complete shape transformation but it would effectively also reduce membrane permeability and enhance osmotic pressure
  • , as temperature is a factor in the van ‘t Hoff formula for osmotic pressure [21]. Additionally, dehydration strengthens polysarcosine chains interactions [16], potentially rendering the membrane too rigid for shape transformation. This means that the heating of the vesicles made with polysarcosine
  • the thermogram unveiled a peak during the initial heating cycle, spanning from 40 °C to 90 °C (Supporting Information File 1, Figure S18). This peak corresponds with the dehydration temperature of polysarcosine, suggesting its role in facilitating subsequent shape manipulation [16]. The assembly of
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Published 08 Jan 2025

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

  • Laura D’Andrea and
  • Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

Graphical Abstract
  • identify the highest yielding reaction times (reaction stopped at 10, 15, 30, 45, 60, 75, and 90 minutes) revealed that longer stirring when heating is applied is not beneficial. In general, soon after the optimal reaction times indicated in Table 1, the yield progressively decreases when the reaction
  • structures both prior to and following the production of the target compounds. The application of mild heating is crucial to reach full conversion of the starting materials in the times indicated in Table 1. However, conversion to the desired products is also achievable at room temperature over 18 hour
  • stirring with minor yield loss. Increasing the heating temperature up to 110 °C does not lead to increased product yields (for more information on the optimization process, see Supporting Information File 1, page S19). The use of diethylenetriamine (DETA) was also investigated to evaluate its impact on the
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Published 07 Jan 2025

Emerging trends in the optimization of organic synthesis through high-throughput tools and machine learning

  • Pablo Quijano Velasco,
  • Kedar Hippalgaonkar and
  • Balamurugan Ramalingam

Beilstein J. Org. Chem. 2025, 21, 10–38, doi:10.3762/bjoc.21.3

Graphical Abstract
  • to increase the experimental throughput. Commonly, batch platforms include a liquid handling system for setting up reactions based on a plunger pump (e.g., syringe, pipette), a reactor capable of heating and mixing, and in-line/online analytical tools. HTE in batch excels in the control of
  • , stirring, heating, and cooling modules for enhanced versatility. In addition, the platform is capable of performing under inert and low-pressure atmospheres, handling separation steps, and pressure sensing for reaction monitoring. Its efficacy and robustness were confirmed through the successful synthesis
  • laboratory (ASL) was designed and built by Eli Lilly [33]. This state-of-the-art facility allowed for heating, cryogenic conditions, microwaving, high-pressure reactions, evaporation, and workup, empowering researchers to conduct an extensive array of chemical reactions. The ASL comprises of three bench
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Published 06 Jan 2025

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

  • Yang Chen,
  • Jiao He,
  • Hang Lin,
  • Hai-Feng Wang,
  • Ping Hu,
  • Bi-Qin Wang,
  • Ke-Qing Zhao and
  • Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

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  • Supporting Information File 1 (Figure S36). Comparative bar graph summarizing the thermal behavior of Fn, BTP6, and PHn derivatives (2nd heating DSC data). Representative S/WAXS patterns of Fn and Gnm compounds. Absorption (a) and emission (b) spectra of F6 and G66, measured in different solvents at a
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Published 16 Dec 2024

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

  • Radell Echemendía,
  • Carlee A. Montgomery,
  • Fabio Cuzzucoli,
  • Antonio C. B. Burtoloso and
  • Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

Graphical Abstract
  •  1, entries 9–12). We attempted to decrease the reaction time by increasing the temperature, but these changes resulted in decreased yields of 3a (Table 1, entries 13 and 14). Surprisingly, when using microwave (MW) heating at 70 ⁰C for 10 min in ACN, product 3a was formed in 74% yield (Table 1
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Published 04 Dec 2024
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  • )rotaxane framework The rotaxane framework is often deployed as a molecular device in which the positional relationship between the axle and wheel is controlled by external stimuli [14][32]. Acid–base, photoisomerization, redox, ion recognition, solvent polarity, or heating treatment is generally used for
  • visible-light irradiation or heating, CD was moved back to the azobenzene moiety, and the entire process was reversible. This system was further developed in 2005 by introducing bipyridinium moieties to implement the selective transfer of the wheel via heating or light irradiation (Figure 5B) [57]. During
  • the urea end-capping synthesis method (Figure 9) [46][47]. First, [3]rotaxane 3 synthesized using 2-bromophenyl isocyanate (yield: 73%) was confirmed to be a size-complementary rotaxane whose desilippage was observed in a DMSO solvent by heating at approximately 80 °C (Figure 9A,B). As the
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Published 19 Nov 2024

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

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  • heated to temperature T2 (136–205 °C, see Supporting Information File 1) until 20–40% mass loss of original weight. Based on this data, the following decomposition mechanism is proposed (Figure 4a): MS, 1H and 31P NMR analysis after heating to T1 showed the presence of (methyloxycarbonylmethyl
  • ) results in (methoxycarbonyl(iodo)methyl)triphenylphosphonium salt 5 (observed by MS). Deiodination or decarboxylation from this intermediate afford 6 and 7, respectively. After heating to T2, (methyl)triphenylphosphonium salt 8 is observed, which may be formed from 6 and 7 by decarboxylation and loss of
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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

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  • -pulling groups at the para and meta-position of the aryl group were compatible with the reaction leading to moderate to good yields of products. In contrast, products with substitutions at the ortho position were obtained only after heating the reaction mixture to 60 °C. These compounds were further
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Published 13 Nov 2024

Multicomponent synthesis of α-branched amines using organozinc reagents generated from alkyl bromides

  • Baptiste Leroux,
  • Alexis Beaufils,
  • Federico Banchini,
  • Olivier Jackowski,
  • Alejandro Perez-Luna,
  • Fabrice Chemla,
  • Marc Presset and
  • Erwan Le Gall

Beilstein J. Org. Chem. 2024, 20, 2834–2839, doi:10.3762/bjoc.20.239

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  • species 2 were collected using a syringe and allowed to react with an amine 3 and an aldehyde 4 under moderate heating (Scheme 2). The multicomponent couplings proceeded smoothly, with an acceptable yield of the α-branched amine being obtained after 3 h at 50 °C. A range of secondary amines as well as
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Published 07 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

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  • heating, acting both as base and acid. This dual role activates the amide moiety and the ethynyl group, respectively. Using larger amounts of ammonium acetate substantially prolongs the reaction time due to its dissociation properties. Consequently, the yield of 5a increased to 92% by increasing the
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Published 06 Nov 2024

Mechanochemical difluoromethylations of ketones

  • Jinbo Ke,
  • Pit van Bonn and
  • Carsten Bolm

Beilstein J. Org. Chem. 2024, 20, 2799–2805, doi:10.3762/bjoc.20.235

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  • footprint of organic reactions [12][13]. Beyond environmental benefits and enhanced human safety, mechanochemical reactions often feature shorter reaction times, eliminate the need for external heating, and offer alternative product selectivity [3][14]. In general, such reactions are characterized by the
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Published 04 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
  • . Coalescence of the β-ethyl resonances was observed when heating the sample to 70 °C and the same 1H NMR spectrum was observed after subsequent cooling of the sample as before heating. This indicates the thermodynamically favored dimeric structure to reassemble when cooling, reverting to the previous NMR trace
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Published 04 Nov 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
  • standing. Also, it has been reported that the generation of the hydroperoxide may be accelerated by heating the solvent under open atmospheric conditions [19]. We envisaged that such autooxidation of THF [20] will produce THF hydroperoxide, and this will facilitate the transformation of 3-arylbenzofuran-2
  • use of a hydroperoxide generating solvent made the protocol operationally simple. To investigate the generality of the protocol, the previously synthesized 3-arylbenzofuran-2(3H)-ones 3aa–ka were treated with 1.0 equiv Cs2CO3 in THF under open atmospheric heating. As revealed in Scheme 2, the reaction
  • a bulky substitution at the 7-position of the benzofuranone also hinders the formation of 2-hydroxybenzophenone, we prepared 3,7-diphenylbenzofuran-2-one (3ma). However, on heating 3ma with Cs2CO3 in THF, the corresponding benzophenone 4ma was obtained, which confirmed that a bulky substituent in
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Published 21 Oct 2024

Deciphering the mechanism of γ-cyclodextrin’s hydrophobic cavity hydration: an integrated experimental and theoretical study

  • Stiliyana Pereva,
  • Stefan Dobrev,
  • Tsveta Sarafska,
  • Valya Nikolova,
  • Silvia Angelova,
  • Tony Spassov and
  • Todor Dudev

Beilstein J. Org. Chem. 2024, 20, 2635–2643, doi:10.3762/bjoc.20.221

Graphical Abstract
  • upon heating. Conclusion Using experimental and computational methods as well as available literature data, the present study reliably estimates the number of water molecules present in γ-CD, their preferable binding position, and thermal stability. Comparison with the other cyclodextrins revealed that
  • Differential Scanning Calorimeter. The samples were placed in aluminum pans and heated in the temperature range between 300–440 K at a constant rate of 10 °C min−1 under pure nitrogen atmosphere. Similarly, thermogravimetric measurements were conducted using DTA/TG (TA-SDT 600) at the same heating rate and
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Published 17 Oct 2024
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