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Search for "thermal stability" in Full Text gives 237 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Functionalization of graphene: does the organic chemistry matter?

  • Artur Kasprzak,
  • Agnieszka Zuchowska and
  • Magdalena Poplawska

Beilstein J. Org. Chem. 2018, 14, 2018–2026, doi:10.3762/bjoc.14.177

Graphical Abstract
  • and hydrogen bonding-dependent adsorption of glucose on the RGO surface results in a shift of the absorption bands coming from the C=O of RGO (from 1724 cm−1 to 1735 cm−1). Another consideration is that this process further influences the obtained material’s morphology, properties and thermal
  • stability [41][42]. Additionally, some researchers have used the acid catalysis [39] or grinding-induced process [40] for the esterification reaction, and the changes in the spectra (e.g., IR, XPS) were not prominent enough to imply the formation of covalent ester-type linkages. In the grinding-induced case
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Published 02 Aug 2018

Hyper-reticulated calixarene polymers: a new example of entirely synthetic nanosponge materials

  • Alberto Spinella,
  • Marco Russo,
  • Antonella Di Vincenzo,
  • Delia Chillura Martino and
  • Paolo Lo Meo

Beilstein J. Org. Chem. 2018, 14, 1498–1507, doi:10.3762/bjoc.14.127

Graphical Abstract
  • [21][22][23][24][25][26][27]. The properties of CyNSs, in terms of physical and mechanical features, porosity, thermal stability and adsorption or release abilities, may be modulated up to a certain extent by a sensible choice of the linker unit, depending on its length and possible functionalization
  • surface. Finally, DSC experiments were performed in order to evaluate the behavior on heating and the thermal stability of the materials. We found out that both the parent Ca-OP monomer and the CaNSs materials decompose at ca. 230 °C. pH Dependent absorption abilities The possible pH dependent abilities
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Published 20 Jun 2018

Recent advances in phosphorescent platinum complexes for organic light-emitting diodes

  • Cristina Cebrián and
  • Matteo Mauro

Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124

Graphical Abstract
  • complexes exhibited high thermal stability since thermogravimetric analysis (TGA) showed a weight loss of only 5% at temperatures in the range 436–463 °C. An intense and structured emission in the green region with λem = 500–507 nm and PLQY = 0.6–0.78 was recorded when the complexes were used as dopant in
  • and high thermal stability. Unfortunately, going from dilute solution to neat solid-state samples, PLQY values dramatically dropped to values as low as 0.10–0.02 that might point to strong intermolecular interaction and TTA phenomena. The tendency toward aggregation for complex 44 and 46 in condensed
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Published 18 Jun 2018

Oligonucleotide analogues with cationic backbone linkages

  • Melissa Meng and
  • Christian Ducho

Beilstein J. Org. Chem. 2018, 14, 1293–1308, doi:10.3762/bjoc.14.111

Graphical Abstract
  • reported to be above 80 °C whereas a comparable DNA–DNA duplex was only stable up to 13 °C. DNmt-T5 complexes with native RNA-APoly showed an even higher thermal stability. Job plot analysis revealed the formation of triple-stranded complexes between the DNmt pentamer and DNA-APoly or RNA-APoly
  • . Furthermore, a pronounced drop in thermal stability of DNmt–DNA complexes containing 50% T–C mismatches and also for congeners containing 20% T–C mismatches was described [71]. In CD spectroscopic studies performed on the thymidinyl DNmt pentamer, Bruice et al. further confirmed the base-pairing specificity
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Published 04 Jun 2018

London dispersion as important factor for the stabilization of (Z)-azobenzenes in the presence of hydrogen bonding

  • Andreas H. Heindl,
  • Raffael C. Wende and
  • Hermann A. Wegner

Beilstein J. Org. Chem. 2018, 14, 1238–1243, doi:10.3762/bjoc.14.106

Graphical Abstract
  • [12] and show reversible isomerization from the thermally stable E- to the Z-isomer upon irradiation with UV light. The metastable Z-azobenzene re-isomerizes to the E-conformer either thermally or upon irradiation with visible light [13][14]. Interestingly, the thermal stability of azobenzene isomers
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Published 29 May 2018

Two novel blue phosphorescent host materials containing phenothiazine-5,5-dioxide structure derivatives

  • Feng-Ming Xie,
  • Qingdong Ou,
  • Qiang Zhang,
  • Jiang-Kun Zhang,
  • Guo-Liang Dai,
  • Xin Zhao and
  • Huai-Xin Wei

Beilstein J. Org. Chem. 2018, 14, 869–874, doi:10.3762/bjoc.14.73

Graphical Abstract
  • . Moreover, their fluorescence emission peaks are in the blue fluorescence region at 408 nm and the fluorescence quantum efficiency (Φ) of CEPDO and CBPDO were 62.5% and 59.7%, respectively. Both CEPDO and CBPDO showed very high thermal stability with decomposition temperatures (Td) of 409 and 396 °C as well
  • time, the photophysical properties, electrochemical properties and their thermal stability were studied and the expected results were obtained. Results and Discussion Synthesis and theoretical calculations The synthesis route for CEPDO and CBPDO is shown in Scheme 1. The detailed synthesis procedures
  • scanning calorimetry (DSC) under nitrogen atmosphere at a scanning rate of 10 °C/min and the results are shown in Figure 4. Both CEPDO and CBPDO show very high thermal stability with decomposition temperatures (Td) of 409 and 396 °C and glass transition temperatures (Tg) of 167 and 138 °C, respectively
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Published 17 Apr 2018

Mannich base-connected syntheses mediated by ortho-quinone methides

  • Petra Barta,
  • Ferenc Fülöp and
  • István Szatmári

Beilstein J. Org. Chem. 2018, 14, 560–575, doi:10.3762/bjoc.14.43

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  • reactions is definitely more advantageous. Ionic liquids have also attracted considerable attention due to their „green chemistry” values, including reusability, high thermal stability and non-inflammability. Hajipour et al. reported the one-pot synthesis of 1-amidoalkyl-2-naphthols catalysed by N-(4
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Published 06 Mar 2018

Polarization spectroscopy methods in the determination of interactions of small molecules with nucleic acids – tutorial

  • Tamara Šmidlehner,
  • Ivo Piantanida and
  • Gennaro Pescitelli

Beilstein J. Org. Chem. 2018, 14, 84–105, doi:10.3762/bjoc.14.5

Graphical Abstract
  • increase in the cuvette, usually best seen in the long-wavelength range of the spectrum, is a clear evidence of precipitation or colloid/aggregate formation in the cuvette, which completely hampers further experiments. The characterization of the thermal stability of the ligand solution by collecting it’s
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Published 08 Jan 2018

Exploring mechanochemistry to turn organic bio-relevant molecules into metal-organic frameworks: a short review

  • Vânia André,
  • Sílvia Quaresma,
  • João Luís Ferreira da Silva and
  • M. Teresa Duarte

Beilstein J. Org. Chem. 2017, 13, 2416–2427, doi:10.3762/bjoc.13.239

Graphical Abstract
  • coordination networks of pharmaceuticals involving lanthanides, showing different types of architectures based on mono-, di-, tri- and hexametallic centers and 1D polymeric chains. These new compounds proved to be unstable under shelf conditions. With regard to their thermal stability these compounds lose
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Published 14 Nov 2017

Synthesis, effect of substituents on the regiochemistry and equilibrium studies of tetrazolo[1,5-a]pyrimidine/2-azidopyrimidines

  • Elisandra Scapin,
  • Paulo R. S. Salbego,
  • Caroline R. Bender,
  • Alexandre R. Meyer,
  • Anderson B. Pagliari,
  • Tainára Orlando,
  • Geórgia C. Zimmer,
  • Clarissa P. Frizzo,
  • Helio G. Bonacorso,
  • Nilo Zanatta and
  • Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 2396–2407, doi:10.3762/bjoc.13.237

Graphical Abstract
  • high thermal stability and low volatility) of ILs can be considered. Reactions in [BMIM][BF4] and [HMIM][TsO] using p-toluenesulfonic acid (p-TsO) as a catalyst were unsuccessful and have been omitted from Table 1. The best conditions that were found for 1a and 5-aminotetrazole (2) were used for the
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Published 10 Nov 2017

Structure–property relationships and third-order nonlinearities in diketopyrrolopyrrole based D–π–A–π–D molecules

  • Jan Podlesný,
  • Lenka Dokládalová,
  • Oldřich Pytela,
  • Adam Urbanec,
  • Milan Klikar,
  • Numan Almonasy,
  • Tomáš Mikysek,
  • Jaroslav Jedryka,
  • Iwan V. Kityk and
  • Filip Bureš

Beilstein J. Org. Chem. 2017, 13, 2374–2384, doi:10.3762/bjoc.13.235

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  • °C, respectively. The 2,5-thienylene linker decreased the melting point approximately by 40 °C (e.g., 2a/4a with Tm = 244/200 °C). End-capping the DPP derivative with a ferrocene donor brings improved thermal stability (e.g., compound 5b with the second highest Tm and Td values within the series b
  • in modular way prepared by Suzuki–Miyaura, Migita–Stille, and Sonogashira cross-coupling reactions. The chromophores differ in the π-system extension as well as in the peripheral substitution. The thermal stability of 1–5 is mostly affected by the presence of acetylene linkers, 1,4-phenylene and 2,5
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Published 08 Nov 2017

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

  • Satoru Mori and
  • Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

Graphical Abstract
  • TFEO-ZnPc into a fluoropolymer markedly improves its thermal stability. In addition, the TFEO-ZnPc-supported fluoropolymer showed significantly lower fluorescence than monomeric TFEO-ZnPc. This suggests a strong electronic interaction among TFEO-Pc units, allowing for its application in photonic
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Published 27 Oct 2017

Novel approach to hydroxy-group-containing porous organic polymers from bisphenol A

  • Tao Wang,
  • Yan-Chao Zhao,
  • Li-Min Zhang,
  • Yi Cui,
  • Chang-Shan Zhang and
  • Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 2131–2137, doi:10.3762/bjoc.13.211

Graphical Abstract
  • obtained PPOPs are shown in the Scheme 1. All of the polymers are stable and insoluble in common organic solvents such as dichloromethane, ethanol, and acetone. Furthermore, the as-prepared materials exhibit a high thermal stability according to the results of TGA (Supporting Information File 1, Figure S1
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Published 12 Oct 2017

An efficient Pd–NHC catalyst system in situ generated from Na2PdCl4 and PEG-functionalized imidazolium salts for Mizoroki–Heck reactions in water

  • Nan Sun,
  • Meng Chen,
  • Liqun Jin,
  • Wei Zhao,
  • Baoxiang Hu,
  • Zhenlu Shen and
  • Xinquan Hu

Beilstein J. Org. Chem. 2017, 13, 1735–1744, doi:10.3762/bjoc.13.168

Graphical Abstract
  • polymers from the polymerization of ethylene oxide [67]. Owing to their significant advantages, including widely commercial availability, biocompatibility, chemical and thermal stability and ease to be derived, PEGs have been widely used as phase-transfer catalysts (PTC) or in the preparation of water
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Published 21 Aug 2017

Block copolymers from ionic liquids for the preparation of thin carbonaceous shells

  • Sadaf Hanif,
  • Bernd Oschmann,
  • Dmitri Spetter,
  • Muhammad Nawaz Tahir,
  • Wolfgang Tremel and
  • Rudolf Zentel

Beilstein J. Org. Chem. 2017, 13, 1693–1701, doi:10.3762/bjoc.13.163

Graphical Abstract
  • energy is needed to overcome the lattice energy and melt the salt. Ion liquids are also called “green solvents”, because of their low vapor pressure, fire resistance and thermal stability [4]. Beside this, they have a high ionic conductivity, large heat capacity and good thermal and chemical stability [5
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Published 16 Aug 2017

Mechanochemical borylation of aryldiazonium salts; merging light and ball milling

  • José G. Hernández

Beilstein J. Org. Chem. 2017, 13, 1463–1469, doi:10.3762/bjoc.13.144

Graphical Abstract
  • heating. NMR analysis of the molten 1d revealed the presence of 1-fluoro-4-iodobenzene (for details, see Supporting Information File 1). Therefore, the difference in melting point temperatures of the substrates and their thermal stability could have a direct correlation with the observed reactivity in the
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Published 26 Jul 2017

Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction

  • Qing Yin,
  • Qi Chen,
  • Li-Can Lu and
  • Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120

Graphical Abstract
  • and SugPOP-2 are shown in Figures S2 and S3 (Supporting Information File 1) and show similar resonance intensities to SugPOP-3. All of the polymer samples show some common properties of cross-linked polymers such as stability and insolubility in common solvents. The thermal stability of SugPOP-1–3 was
  • characterized by thermogravimetric analysis (TGA) under nitrogen atmosphere (Figure S4, Supporting Information File 1). The TGA plots show that the decomposition temperature of the polymers is at about 300 °C and there is 35% mass loss when the temperature reaches 800 °C, indicating good thermal stability of
  • diffraction peaks suggest the formation of small-sized AgNPs. The actual loading capacity of Ag is 5.4 wt % as discerned by TGA under air atmosphere. Meanwhile, the AgNPs/SugPOP-1 composite exhibits about 2% mass loss at 310 °C and good thermal stability (Figure S7 in Supporting Information File 1). The
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Published 22 Jun 2017

G-Protein coupled receptors: answers from simulations

  • Timothy Clark

Beilstein J. Org. Chem. 2017, 13, 1071–1078, doi:10.3762/bjoc.13.106

Graphical Abstract
  • , polar fragment such as the T4 lysozyme [10][11] or other suitable protein fragments [12]. Other techniques used to obtain GPCR crystals include mutations to enhance the thermal stability [13], solubilization with custom detergents [14] or in conjunction with high-affinity ligands, which promote one
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Published 02 Jun 2017

Aggregation behaviour of a single-chain, phenylene-modified bolalipid and its miscibility with classical phospholipids

  • Simon Drescher,
  • Vasil M. Garamus,
  • Christopher J. Garvey,
  • Annette Meister and
  • Alfred Blume

Beilstein J. Org. Chem. 2017, 13, 995–1007, doi:10.3762/bjoc.13.99

Graphical Abstract
  • -C18pPhC18-PC is partially miscible with saturated phosphatidylcholines; however, closed lipid vesicles with an increased thermal stability were not found. Instead, bilayer fragments and disk-like aggregates are formed. Keywords: aggregation behaviour; bolaamphiphiles; bolalipids; membrane lipids; mixing
  • -C16pPhC16-PC [36], which self-assembles at room temperature into small ellipsoidal micelles, and to PC-C17pPhC17-PC [35] that forms nanofibres with a significantly reduced thermal stability compared to PC-C32-PC. Unfortunately, the insertion of PC-C17pPhC17-PC into phospholipid bilayers composed of, e.g
  • formation of disk-like aggregates in mixtures with DPPC and DSPC, respectively, with partly increased thermal stability [34]. The mixing behaviour of PC-C18pPhC18-PC with phosphatidylcholines was now studied by means of DSC and TEM. Additionally, one example of a bolalipid/phospholipid mixture was further
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Published 23 May 2017

Molecular-level architectural design using benzothiadiazole-based polymers for photovoltaic applications

  • Vinila N. Viswanathan,
  • Arun D. Rao,
  • Upendra K. Pandey,
  • Arul Varman Kesavan and
  • Praveen C. Ramamurthy

Beilstein J. Org. Chem. 2017, 13, 863–873, doi:10.3762/bjoc.13.87

Graphical Abstract
  • polymers was concentrated and precipitated from methanol. The number-averaged molecular weight (Mn), weight-averaged molecular weight (Mw) and polydispersity index (PDI) of the polymers were calculated and are summarized in Table S1 (see Supporting Information File 1). All polymers showed excellent thermal
  • stability with onset decomposition temperature of >410 °C. Computational modeling of the three polymers was performed to gain insight into the molecular energy levels along with band gaps using density functional theory (DFT) at the B3LYP/6-31G (d,p) level as implemented in Gaussian-09 software [37]. For
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Published 10 May 2017

Exploring endoperoxides as a new entry for the synthesis of branched azasugars

  • Svenja Domeyer,
  • Mark Bjerregaard,
  • Henrik Johansson and
  • Daniel Sejer Pedersen

Beilstein J. Org. Chem. 2017, 13, 644–647, doi:10.3762/bjoc.13.63

Graphical Abstract
  • was encouraging and gave access to a variety of novel protected azasugar precursors. We conclude that the choice of amine and dihydroxy protecting groups can have an impact on the success of the endoperoxide synthesis and its thermal stability, and that employing phthalimide and acetonide groups for N
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Published 03 Apr 2017

Fast and efficient synthesis of microporous polymer nanomembranes via light-induced click reaction

  • Qi An,
  • Youssef Hassan,
  • Xiaotong Yan,
  • Peter Krolla-Sidenstein,
  • Tawheed Mohammed,
  • Mathias Lang,
  • Stefan Bräse and
  • Manuel Tsotsalas

Beilstein J. Org. Chem. 2017, 13, 558–563, doi:10.3762/bjoc.13.54

Graphical Abstract
  • storage and separation as well as in organic electronics [8]. Among the microporous materials, conjugated microporous polymers (CMPs) [9][10] or porous aromatic frameworks (PAF) [11] have favorable properties for many applications, since they combine a high chemical and thermal stability, which is
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Published 17 Mar 2017

Dimerization reactions of aryl selenophen-2-yl-substituted thiocarbonyl S-methanides as diradical processes: a computational study

  • Michael L. McKee,
  • Grzegorz Mlostoń,
  • Katarzyna Urbaniak and
  • Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 410–416, doi:10.3762/bjoc.13.44

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  • convenient access comprises the treatment of a C=S substrate with diazomethane or its derivatives. Depending on the substitution pattern, 2,5-dihydro-1,3,4-thiadiazoles 2 display different thermal stability. Whereas sterically bulky aliphatic substituents increase the temperature required for the
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Published 03 Mar 2017

Highly reactive, liquid diacrylamides via synergistic combination of spatially arranged curing moieties

  • Maximilian Maier,
  • Magnus S. Schmidt,
  • Markus Ringwald and
  • Christoph P. Fik

Beilstein J. Org. Chem. 2017, 13, 372–383, doi:10.3762/bjoc.13.40

Graphical Abstract
  • of new monomers and crosslinkers remained limited [4]. Mono-, di-, tri- and multifunctional (meth)acrylates are among the first choices for photopolymerized mixtures as they exhibit a favorable balance between reactivity and thermal stability upon storage [5][6][7]. Moreover, they comprise
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Published 27 Feb 2017

Highly bulky and stable geometry-constrained iminopyridines: Synthesis, structure and application in Pd-catalyzed Suzuki coupling of aryl chlorides

  • Yi Lai,
  • Zhijian Zong,
  • Yujie Tang,
  • Weimin Mo,
  • Nan Sun,
  • Baoxiang Hu,
  • Zhenlu Shen,
  • Liqun Jin,
  • Wen-hua Sun and
  • Xinquan Hu

Beilstein J. Org. Chem. 2017, 13, 213–221, doi:10.3762/bjoc.13.24

Graphical Abstract
  • iminopyridylpalladium chlorides were developed. The steric environment adjacent to the nitrogen atom in the pyridine rings and diimine parts enhanced the thermal stability of the palladium species. Bulkier groups at the imino group stabilized the palladium species and the corresponding palladium chlorides showed high
  • under high temperature, if the palladium catalyst is stable enough. The formation of palladium black was observed in reactions of aryl chlorides using the reported palladium catalyst system, which inspired us to improve the thermal stability of the palladium complex. The steric environment adjacent to
  • the nitrogen in pyridine rings and diimine parts enhanced the thermal stability of metal species, albeit under harsh conditions [65][66][67][68]. Therefore, Figure 1 schematically illustrates various substituents of iminopyridines constraining the geometrical influence around the palladium center. In
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Published 03 Feb 2017
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