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Search for "DSC" in Full Text gives 138 result(s) in Beilstein Journal of Organic Chemistry.

Synthesis of polydicyclopentadiene using the Cp2TiCl2/Et2AlCl catalytic system and thin-layer oxidation of the polymer in air

  • Zhargolma B. Bazarova,
  • Ludmila S. Soroka,
  • Alex A. Lyapkov,
  • Мekhman S. Yusubov and
  • Francis Verpoort

Beilstein J. Org. Chem. 2019, 15, 733–745, doi:10.3762/bjoc.15.69

Graphical Abstract
  • a monomer unit of the polymer: Accumulation of peroxides in the polymer layer is confirmed by DSC analysis of films subjected to air oxidation for 700 hours (Figure 11). From the DSC curve (Figure 11), at 140 °C an exothermic peak can be observed corresponding to the decomposition of peroxides
  • can correspond to the processes of oxidation of -C=C- bonds in the polymer chain due to adsorbed oxygen. In the DSC of unexposed film, this peak is absent. However, the DSC of unexposed film in air atmosphere (Figure 12) shows that the oxidation and decomposition of peroxides formed during the
  • performed using a DSC 204 F1 Phoenix (NETZSCH) at a heating rate 10 °С/min with aluminum pans (the lid was manually drilled to ensure the access of argon). The DSC instrument was first calibrated with an indium standard. Measurements were carried out under an inert argon (or air) atmosphere at a flow rate
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Published 20 Mar 2019

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

  • Andrejs Šišuļins,
  • Jonas Bucevičius,
  • Yu-Ting Tseng,
  • Irina Novosjolova,
  • Kaspars Traskovskis,
  • Ērika Bizdēna,
  • Huan-Tsung Chang,
  • Sigitas Tumkevičius and
  • Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

Graphical Abstract
  • refrigerator at −20 °C for a prolonged period of time. In addition, DSC measurements for compounds 2a–c were done. Diazides 2a–c melted at 67 °C, 75 °C and 82 °C, respectively, and showed an exothermic effect only if heated above 190 °C (Figures S5–S7 in Supporting Information File 1). In the 7-deaza series
  • , 10a–f, 8a–f and 11a–f.a Emission maxima and quantum yields of compound 8c and 11c in solvents of different polarity. Supporting Information Supporting Information File 20: Full experimental procedures, emission spectra, DSC data, and copies of 1H and 13C NMR spectra. Acknowledgements This work is
  • emission spectra and Dr. J. Zicāns and R. Merijs Meri for DSC measurements. Copyrights to the picture “business people greet” used in the graphical abstract belong to Publitek, Inc. dba GoGraph (https://www.gograph.com/).
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Published 15 Feb 2019

Olefin metathesis in multiblock copolymer synthesis

  • Maria L. Gringolts,
  • Yulia I. Denisova,
  • Eugene Sh. Finkelshtein and
  • Yaroslav V. Kudryavtsev

Beilstein J. Org. Chem. 2019, 15, 218–235, doi:10.3762/bjoc.15.21

Graphical Abstract
  • change in the course of MCM. Nevertheless, it can be successfully implemented using a complex of NMR, GPC, and DSC methods. As a rule, the parent polymers are characterized by different molecular masses, which allow using GPC to track how two peaks in the chromatogram merge into one with conversion. If
  • the initial polymers display different glass transition temperatures, DSC can be also used to monitor the kinetics (Figure 5). At the beginning of the MCM reaction, two Tg values are observed which get closer and finally merge into one, when long sequences of chemically identical units stemming from
  • crystallinity and melting temperature are higher for the copolymers with longer COE blocks. Copolymer crystallinity can be studied in detail by combining WAXD and DSC methods, including recently emerged technique of thermal fractionation by successive self-nucleation and annealing [84][92][102][103]. It was
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Published 24 Jan 2019

A general and atom-efficient continuous-flow approach to prepare amines, amides and imines via reactive N-chloramines

  • Katherine E. Jolley,
  • Michael R. Chapman and
  • A. John Blacker

Beilstein J. Org. Chem. 2018, 14, 2220–2228, doi:10.3762/bjoc.14.196

Graphical Abstract
  • -toluenesulfonamide (11) was investigated as substrate. Differential scanning calorimetry (DSC) was used to assess the thermal stability of 11, which melts at 78 °C and decomposes between 160–200 °C. This profile peaks at 188 °C, corresponding to an enthalpy of decomposition of −84.7 kJ mol−1 (see Supporting
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Published 24 Aug 2018

Synthesis of pyrimido[1,6-a]quinoxalines via intermolecular trapping of thermally generated acyl(quinoxalin-2-yl)ketenes by Schiff bases

  • Svetlana O. Kasatkina,
  • Ekaterina E. Stepanova,
  • Maksim V. Dmitriev,
  • Ivan G. Mokrushin and
  • Andrey N. Maslivets

Beilstein J. Org. Chem. 2018, 14, 1734–1742, doi:10.3762/bjoc.14.147

Graphical Abstract
  • )ketene. STA plot of thermolysis of PQT 1a. Blue solid curve: DSC; green solid curve: TG; greed dashed curve: DTG; violet solid curve: MID (m/z = 28); brown solid curve: MID (m/z = 44); heating rate: 5 °C/min. Scope of the intermolecular trapping of ketenes generated from PQTs 1a–h by Schiff bases 2a–d
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Published 11 Jul 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
  • different alkyl diazides A1–A4 (Scheme 1b), in which the two azido groups are separated by spacers having different length and rigidity. The materials obtained were characterized by means of combined spectroscopic (FTIR, solid state 13C{1H} CP-MAS NMR), calorimetric (DSC) and imaging (SEM) techniques. Then
  • the CuAAC coupling reaction to proceed up to a lesser extent during the polymer network formation process. SEM and DSC characterization Morphological characterization of the materials was accomplished by means of SEM techniques. A selection of micrographs is reported in Figure 3. The materials show
  • 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

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
  • 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
  • ). Cyclic voltammograms for CEPDO and CBPDO in DCM solution. DSC and TGA curves of CEPDO and CBPDO. Synthetic routes of CEPDO and CBPDO. Photophysics, electrochemical and thermal properties of CEPDO and CBPDO. Supporting Information Supporting Information File 14: Experimental part and copies of NMR
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Published 17 Apr 2018

D–A–D-type orange-light emitting thermally activated delayed fluorescence (TADF) materials based on a fluorenone unit: simulation, photoluminescence and electroluminescence studies

  • Lin Gan,
  • Xianglong Li,
  • Xinyi Cai,
  • Kunkun Liu,
  • Wei Li and
  • Shi-Jian Su

Beilstein J. Org. Chem. 2018, 14, 672–681, doi:10.3762/bjoc.14.55

Graphical Abstract
  • efficiency of the OLEDs based on conventional fluorescent materials. Results and Discussion 27DACRFT 1 and 36DACRFT 2 have similar thermal properties according to thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. They have high decomposition temperatures (Td
  • , corresponding to a 5% weight loss) of 361 and 363 °C, respectively. In addition, no glass-transition temperature (Tg) was found according to their DSC curves. Thanks to their amorphous characteristics, the stability of their morphology and chemical composition can be expected during the evaporation processing
  • NMR spectra were measured on a Bruker NMR spectrometer with tetramethylsilane (TMS) as the internal standard. TGA and DSC measurements were performed on a Netzsch TG 209 and a Netzsch DSC 209 under N2, respectively. A CHI600D electrochemical work station with a platinum working electrode and a
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Published 22 Mar 2018

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

Graphical Abstract
  • were further investigated by differential scanning calorimetry (DSC), electrochemistry, absorption and emission spectra, DFT calculations, and THG measurements. Results and Discussion Synthesis of DPP derivatives 1–5 According to the π-linker structure, two series of target chromophores a and b can be
  • scanning calorimetry (DSC). Figure 2 shows the thermograms of the representative compounds 4a and 4b while Table 1 lists the measured melting temperatures (Tm) and temperatures of thermal decomposition (Td). The measured melting points of derivatives in series a and b range from 200 to 261 °C and from 142
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Published 08 Nov 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
  • of the reaction mixture seemed homogeneous. Differential scanning calorimetry (DSC) analysis of the aryldiazonium salts 1a–d revealed that 1a–c melt followed by decomposition of the samples. However, the DSC profile of the iodobenzenediazonium salt 1d showed a direct thermal decomposition upon
  • decomposition at 423 K, turned out difficult (for the DSC traces of 1a–e see Supporting Information File 1). After 2 h of milling/irradiation the corresponding product 3e was obtained in moderate yield. In general, after the milling/irradiation experiments no aryldiazonium salt was observed in the reaction
  • . bAfter column chromatography. Screening of the reaction conditions.a Borylation of aryl diazonium salts 1 with 2.a Supporting Information Supporting Information File 194: Experimental procedures, experimental set-ups and characterization data, NMR spectra, and DSC traces. Acknowledgements This research
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Published 26 Jul 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
  • was studied as a function of temperature using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, and small angle neutron scattering (SANS). We show that our new bolalipid self-assembles into nanofibres, which transform into
  • flexible nanofibres at 27 °C and further to small elongated micelles at 45 °C. Furthermore, the miscibility of the bolalipid with bilayer-forming phosphatidylcholines (DMPC, DPPC, and DSPC) was investigated by means of DSC, TEM, FTIR, and small angle X-ray scattering (SAXS). We could show that the PC
  • simulations [27]. A temperature increase leads to a transformation of the nanofibres into small micelles and the gel character is lost. This reversible gel/sol transformation is accompanied by a cooperative endothermic transition at Tm = 48 °C, which can be followed by differential scanning calorimetry (DSC
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Published 23 May 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
  • -acryl, N-allyl and/or N-alkyl groups were prepared via two-step syntheses and characterized by 1H/13C NMR-spectra, refractive index (RI) and viscosity measurements. Photo DSC measurements on activated samples provided reactivity parameters ∆Hp, Rp,max and tmax, while FTIR spectra before and after curing
  • pure ethanol or isopropanol – in contrast to compounds 1, 2 and 4–6. Overall, a broad solubility spectrum was found (Table 1). Polymerization behavior Bulk homopolymerization of 1 and 3–6 was monitored by photo-DSC. Curing plots showed a rapid polymerization for 1, 4 and 5 (tmax = 20 s, 24 s and 21 s
  • finger print regime, we can only assume that all three propagation pathways a), b) and c) take place simultaneously. Furthermore, taking in account FTIR and DSC data, we expect that ring formation significantly contributes to the overall reaction enthalpy. It is quite clear, that the combination of
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Published 27 Feb 2017

A new class of organogelators based on triphenylmethyl derivatives of primary alcohols: hydrophobic interactions alone can mediate gelation

  • Wangkhem P. Singh and
  • Rajkumar S. Singh

Beilstein J. Org. Chem. 2017, 13, 138–149, doi:10.3762/bjoc.13.17

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  • acidic solution in contrast to its unstable solution-phase behavior. Differential scanning calorimetry Differential scanning calorimetry (DSC) of gels prepared from TPM-G12 (in propan-1-ol and DMSO) was carried out to study the gel-sol transition (Tgel) behaviour. Figure 3 shows the DSC heating curves of
  • TPM-G12 prepared at 2% w/v. When a system changes from an ordered to a disordered state such as the transition from gel to sol, an endothermic peak in the DSC scan is expected which is observed here [32]. For gel prepared in propan-1-ol, the Tgel (melting of gel) is observed to be 97 °C, whereas for
  • DMSO gel the value is 104 °C. Gel melting profile for propan-1-ol gel is much sharper compared to DMSO gel. It may also be noted here that the Tgel determined from DSC is somewhat higher in comparison to values obtained from the dropping ball method (Figure 2). Gel morphologies To understand the
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Published 23 Jan 2017

Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids

  • Naganna Narra,
  • Shiva Shanker Kaki,
  • Rachapudi Badari Narayana Prasad,
  • Sunil Misra,
  • Koude Dhevendar,
  • Venkateshwarlu Kontham and
  • Padmaja V. Korlipara

Beilstein J. Org. Chem. 2017, 13, 26–32, doi:10.3762/bjoc.13.4

Graphical Abstract
  • calorimetry (DSC). The prepared compounds were also screened for their cytotoxic activity against five cell lines. It was observed that the lipoconjugates of caffeic acid, sinapic acid, ferulic acid, and coumaric acid displayed anticancer and anti-oxidant properties. The anticancer properties of these
  • of the prepared derivatives were studied by the well-established DPPH radical scavenging assay and also by studying the oxidation of linoleic acid using DSC. The DPPH radical is a commercially available stable free radical which is widely used to preliminarily determine the radical scavenging
  • by differential scanning calorimetry (DSC). DSC is a sensitive technique and has been used for investigating the thermotropic properties of several compounds including biological macromolecules, drugs and lipid-based materials for their stability and other characteristics [16]. In the present study
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Published 04 Jan 2017

Effects of solvent additive on “s-shaped” curves in solution-processed small molecule solar cells

  • John A. Love,
  • Shu-Hua Chou,
  • Ye Huang,
  • Guilllermo C. Bazan and
  • Thuc-Quyen Nguyen

Beilstein J. Org. Chem. 2016, 12, 2543–2555, doi:10.3762/bjoc.12.249

Graphical Abstract
  • differential scanning calorimetry (DSC) and compared to its predecessor, p-SIDT(FBTTh2)2. A significant impact on thermal behaviors was observed upon substituting 2-hexylthiophene with octyl cyanoacetate (Supporting Information File 1, Figure S4 and Table S1). As compared to p-SIDT(FBTTh2)2, the melting (Tm
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Published 28 Nov 2016

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

  • Paul B. Geraghty,
  • Calvin Lee,
  • Jegadesan Subbiah,
  • Wallace W. H. Wong,
  • James L. Banal,
  • Mohammed A. Jameel,
  • Trevor A. Smith and
  • David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

Graphical Abstract
  • fully characterized by NMR, IR, UV–vis, TGA, DSC, electrochemistry, photoelectron spectroscopy in air (PESA), and have satisfactory mass spectra and microanalysis results. Full experimental details are described in Supporting Information File 1. Thermal behaviour: TGA and DSC. The thermal behaviour of
  • the BXR and BTxR series has been studied by TGA and DSC. All of the materials show good thermal stability with <5% weight loss below 390 °C, see Supporting Information File 1, Figure S5.1. The phase behaviour was examined by DSC (see Supporting Information File 1, Figure S6.1 for full details) with a
  • the BTxR series results in an intuitive change in the temperatures of the relevant phase transitions, with an inverse correlation observed between alkyl chain length and the specific phase change temperatures. Interestingly, as with BQR the DSC traces of the BTxR analogues reveal markedly different
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Published 02 Nov 2016

Comparing blends and blocks: Synthesis of partially fluorinated diblock polythiophene copolymers to investigate the thermal stability of optical and morphological properties

  • Pierre Boufflet,
  • Sebastian Wood,
  • Jessica Wade,
  • Zhuping Fei,
  • Ji-Seon Kim and
  • Martin Heeney

Beilstein J. Org. Chem. 2016, 12, 2150–2163, doi:10.3762/bjoc.12.205

Graphical Abstract
  • approach was not feasible. In that case, washing with dichloromethane resulted in a demonstrable removal of P3OT homopolymer, as indicated by the differential scanning calorimetry (DSC) thermogram (see Figure 1). Indeed, the melting peak around 190 °C, apparent in the crude block copolymer and attributable
  • amount of P3OT homopolymer that was removed from the crude product upon Soxhlet extraction, as indicated by DSC. In the case of P3OT-b-F-P3OT 1:4, the discrepancy likely arises from the fact that the activated M–H monomer is intrinsically comprised of ca. 20% of a regioisomer which is relatively
  • melting and crystallization temperatures, an effect that was predominantly attributed to the increased backbone planarity and rigidity in combination with the increased aggregation it engenders [42]. In order to probe the crystallization behavior of the block copolymers and blends in thin films, DSC was
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Published 10 Oct 2016

Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

  • Minh Anh Truong and
  • Koji Nakano

Beilstein J. Org. Chem. 2016, 12, 805–812, doi:10.3762/bjoc.12.79

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  • stability of syn-DBBDF 5 and syn-DNBDF 6 were evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The DSC scans of syn-DBBDF 5 and syn-DNBDF 6 showed some transition peaks with the first phase-transition temperature at 20 °C and 45 °C, respectively, in
  • . The highest hole mobility of 1.0 × 10−1 cm2·V−1·s−1 was achieved when using syn-DNBDF-based OFET device. Structures of furan-fused ladder-type π-conjugated compounds. (a) DSC and (b) TG curves of syn-DBBDF 5 and syn-DNBDF 6. (a) UV–vis absorption spectra of syn-DBBDF 5 (blue line) and syn-DNBDF 6 (red
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Published 26 Apr 2016

Amino-functionalized (meth)acryl polymers by use of a solvent-polarity sensitive protecting group (Br-t-BOC)

  • Helmut Ritter,
  • Monir Tabatabai and
  • Markus Herrmann

Beilstein J. Org. Chem. 2016, 12, 245–252, doi:10.3762/bjoc.12.26

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  • , IR, GPC and DSC methods. The kinetics of the deprotection step was followed by 1H NMR spectroscopy. The solvent polarity and neighboring group effects on the kinetics of deprotection are discussed. Keywords: amino group protection; bromo-tert-butyloxycarbonyl; deprotection; free radical
  • spectrometer equipped with a diamond single bounce ATR accessory. The measurements were performed in the range of 400–3000 cm−1 at room temperature. Differential scanning calorimetry (DSC) was performed using a Mettler Toledo DSC 822 instrument equipped with a sample robot TSO801RO. The Apparatus was
  • solid: yield 0.28 g (80%). 1H NMR (300 MHz, CDCl3) δ [ppm] 6.04–5.45 (m, 1H), 4.33–3.97 (m, 2H), 3.90–3.60 (m, 2H), 3.55–3.24 (m, 2H), 2.53–2.12 (m, 1H), 2.09–1.66 (m, 2H), 1.61–1.54 (m, 6H); IR (diamond) [cm−1]: 3359 (m, νN-H), 2955 (m, νC-H), 2930 (m, νC-H), 1698 (w, νC=O), 1516 (s, νN-H); DSC: Tg
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Published 10 Feb 2016

Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds

  • Sophie Letort,
  • Sébastien Balieu,
  • William Erb,
  • Géraldine Gouhier and
  • François Estour

Beilstein J. Org. Chem. 2016, 12, 204–228, doi:10.3762/bjoc.12.23

Graphical Abstract
  • . Various analytical tests were used to access such information in the cases of pesticides [40][41][42]. Phase solubility diagrams could be obtained if changes of their water solubility upon inclusion occur, whereas differential scanning calorimetry (DSC) could be used to discriminate inclusion complexes
  • . However the inclusion complex formation was strengthen by molecular modeling studies with the aromatic group included into the cavity. Finally, DSC curves showed a first endothermic portion starting at 225 °C, typical of a melting process, and a second sharp exothermic decomposition peak, proving the
  • use this technique for routine analysis [48]. Finally the binding constant of the host-guest inclusion complex was reported at 690 ± 140 M−1. Pesticides bearing a non-aromatic group X-ray powder diffraction analysis and DSC validated the formation of a complex between (diethoxyphosphinoximino
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Published 05 Feb 2016

Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L.) and complexation with β-cyclodextrin

  • Daniel I. Hădărugă,
  • Mustafa Ünlüsayin,
  • Alexandra T. Gruia,
  • Cristina Birău (Mitroi),
  • Gerlinde Rusu and
  • Nicoleta G. Hădărugă

Beilstein J. Org. Chem. 2016, 12, 179–191, doi:10.3762/bjoc.12.20

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  • -CD/ASO complexes. The analysis of the complexes by thermogravimetry, differential scanning calorimetry (DSC), and Karl Fischer titration (KFT) as well as the decrease of the “strongly-retained” water content confirm the formation of the inclusion compound. Furthermore, the DSC parameters correlate
  • water and solvent contents in host–guest supramolecular systems by thermal analyses have already been performed for CD/flavonoid and CD/essential oil complexes [37][39]. Differential scanning calorimetry (DSC) analysis DSC can provide further information on the physical and chemical processes occurring
  • during heating, even if the guest compound is not volatile up to the CD degradation temperature. Commercial β-CD has two important DSC peaks corresponding to the release of both “surface” and “strongly-retained” water molecules at 105 °C and to the β-CD decomposition at 319.6 °C (Figure 2). The
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Published 02 Feb 2016

Solving the puzzling competition of the thermal C2–C6 vs Myers–Saito cyclization of enyne-carbodiimides

  • Anup Rana,
  • Mehmet Emin Cinar,
  • Debabrata Samanta and
  • Michael Schmittel

Beilstein J. Org. Chem. 2016, 12, 43–49, doi:10.3762/bjoc.12.6

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  • filtrate was washed with water and dried over MgSO4. After removal of the solvent, column chromatography over silica gel using (n-hexane/ethyl acetate, 1:1, Rf = 0.28) furnished pure product 11 as a dark-green oil. Yield: 354 mg (1.22 mmol, 24%). Tonset = 119 °C (DSC). 1H NMR (400 MHz, CDCl3) δ 2.25 (s, 6H
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Published 11 Jan 2016

Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin

  • Waratchada Sangpheak,
  • Jintawee Kicuntod,
  • Roswitha Schuster,
  • Thanyada Rungrotmongkol,
  • Peter Wolschann,
  • Nawee Kungwan,
  • Helmut Viernstein,
  • Monika Mueller and
  • Piamsook Pongsawasdi

Beilstein J. Org. Chem. 2015, 11, 2763–2773, doi:10.3762/bjoc.11.297

Graphical Abstract
  • diagram showed the formation of a soluble complex of AL type, with higher increase in solubility and stability when hesperetin and naringenin were complexed with RAMEB. Solid complexes were prepared by freeze-drying, and the data from differential scanning calorimetry (DSC) confirmed the formation of
  • dissolution study of flavanones were studied. The formed inclusion complexes were analyzed by DSC. The anti-inflammatory activity of inclusion complexes and the free flavanones were determined by investigating the secretion of certain cytokines in lipopolysaccharide (LPS)-stimulated macrophages. In addition
  • stability was mainly governed by the vdW interaction. DSC analysis To investigate the solid inclusion complex obtained by freeze-drying (Figure 3D and E) and kneading methods (Figure 3F and G), DSC measurements were performed. The thermogram revealed information about the thermal properties of the starting
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Published 29 Dec 2015

Synthesis and photophysical characteristics of polyfluorene polyrotaxanes

  • Aurica Farcas,
  • Giulia Tregnago,
  • Ana-Maria Resmerita,
  • Pierre-Henri Aubert and
  • Franco Cacialli

Beilstein J. Org. Chem. 2015, 11, 2677–2688, doi:10.3762/bjoc.11.288

Graphical Abstract
  • polyrotaxanes than that of 3 non-rotaxane sample was assigned to the different content of threaded TM-βCD or TM-γCD on the copolymer chains (see incomplete coverage determined by 1H NMR). The thermal properties of the copolymers were evaluated by differential scanning calorimetry (DSC) and thermogravimetric
  • . The FTIR (KBr pellets) spectra were obtained on a Bruker Vertex 70 spectrophotometer. The molecular weights of copolymers were determined by GPC in THF by using a Water Associates 440 instrument and polystyrene (Pst) calibrating standards. DSC was performed with a Mettler Toledo DSC-12E calorimeter
  • standard): Mn = 27900 g·mol−1, Mw/Mn = 1.83. 1H NMR spectrum of the polyrotaxane 3·TM-βCD copolymer in CDCl3. DSC traces on second heating scan of 3, 3·TM-βCD and 3·TM-γCD compounds. Optical properties of 3·TM-γCD (dotted line), 3·TM-βCD (dashed line) and 3 (solid line) polymers: absorption spectra at 10−1
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Published 21 Dec 2015

Inclusion complexes of 2-methoxyestradiol with dimethylated and permethylated β-cyclodextrins: models for cyclodextrin–steroid interaction

  • Mino R. Caira,
  • Susan A. Bourne,
  • Halima Samsodien and
  • Vincent J. Smith

Beilstein J. Org. Chem. 2015, 11, 2616–2630, doi:10.3762/bjoc.11.281

Graphical Abstract
  • well-defined and hence met the criterion for subsequent solubility studies. Interaction between 2ME and the amorphous CD derivatives RAMEB and HPBCD PXRD, differential scanning calorimetry (DSC) and FTIR methods were employed to investigate the products of kneading between crystalline 2ME and these
  • amorphous host compounds. (Relevant PXRD traces, DSC traces and FTIR spectra are provided in the Supporting Information File 1). In each case, kneading an equimolar physical mixture of the respective host and 2ME produced an amorphous phase, as evidenced by a PXRD pattern devoid of peaks characteristic of
  • the crystalline component 2ME. Consistent with this, no melting endotherm for 2ME was observed in DSC traces of these preparations, whereas the traces of the corresponding CD-2ME physical mixtures revealed fusion of 2ME at a peak temperature of 188 °C (reported mp 187 °C [9]). Definitive inclusion
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Published 16 Dec 2015
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