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Search for "DSC" in Full Text gives 144 result(s) in Beilstein Journal of Organic Chemistry.

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

Graphical Abstract
  • -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

Graphical Abstract
  • 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

Self-assemblies of γ-CDs with pentablock copolymers PMA-PPO-PEO-PPO-PMA and endcapping via atom transfer radical polymerization of 2-methacryloyloxyethyl phosphorylcholine

  • Jing Lin,
  • Tao Kong,
  • Lin Ye,
  • Ai-ying Zhang and
  • Zeng-guo Feng

Beilstein J. Org. Chem. 2015, 11, 2267–2277, doi:10.3762/bjoc.11.247

Graphical Abstract
  • phosphorylcholine (MPC), these single-chain-stranded loose-fit PPRs were transformed into conformational identical polyrotaxanes (PRs). The structures of the PPRs and PRs were characterized by means of 1H NMR, GPC, 13C CP/MAS NMR, 2D 1H NOESY NMR, FTIR, WXRD, TGA and DSC analyses. Keywords: ATRP; γ-CD; double
  • -PPO-PMA with the varying amount of γ-CDs [10][11][12]. The DSC measurements of PPRs and PRs were also conducted in this study. As shown in Figure 9, BrPEPBr reveals an endothermic peak at 51.8 °C, corresponding to the melting point of the PEO crystalline phase. As for PEP100M, a lower melting point
  • FTIR spectrometer at room temperature using the KBr pellet method. TGA analysis was performed with using a TA SDT 2960 instrument at a heating rate of 10 °C/min from room temperature to 500 °C in a nitrogen atmosphere. DSC measurements were measured on a SHIMADZU DSC-60 differential scanning
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Published 23 Nov 2015

Cross-metathesis of polynorbornene with polyoctenamer: a kinetic study

  • Yulia I. Denisova,
  • Maria L. Gringolts,
  • Alexander S. Peregudov,
  • Liya B. Krentsel,
  • Ekaterina A. Litmanovich,
  • Arkadiy D. Litmanovich,
  • Eugene Sh. Finkelshtein and
  • Yaroslav V. Kudryavtsev

Beilstein J. Org. Chem. 2015, 11, 1796–1808, doi:10.3762/bjoc.11.195

Graphical Abstract
  • MHz (13C NMR); CDCl3 (Aldrich) was used as solvent. Chemical shifts δ were reported in parts per million relative to the residual CHCl3 signal as an internal reference standard. Differential scanning calorimetry (DSC) thermograms were recorded on a Mettler TA 4000 system at a rate of 10 °C/min under
  • mixture to 0.2 mL of ethyl vinyl ether, stirred for 30–40 min at ambient temperature, and concentrated in vacuum, after that CDCl3 was added. For DSC and GPC measurements, the copolymers were precipitated in ethanol and dried as described above. A typical 13C NMR spectrum is shown in Figure 11
  • PCOE with PNB. Static scattering intensity from different CHCl3 solutions: Acknowledgements The authors are thankful to M. Yu. Gorshkova and to G. A. Shandryuk (Topchiev Institute of Petrochemical Synthesis RAS) for performing the GPC and DSC measurements, respectively. The work was partially
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Published 01 Oct 2015

Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

  • Masahiko Iyoda and
  • Masashi Hasegawa

Beilstein J. Org. Chem. 2015, 11, 1596–1613, doi:10.3762/bjoc.11.175

Graphical Abstract
  • (DSC), positive electrode materials for rechargeable batteries, and electrochromic (EC) materials [1]. TTF derivatives are versatile building blocks to form aggregates in the solid state with interesting conducting and magnetic behavior [2]. Although these properties are mainly originated from specific
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Published 10 Sep 2015

Thermal properties of ruthenium alkylidene-polymerized dicyclopentadiene

  • Yuval Vidavsky,
  • Yotam Navon,
  • Yakov Ginzburg,
  • Moshe Gottlieb and
  • N. Gabriel Lemcoff

Beilstein J. Org. Chem. 2015, 11, 1469–1474, doi:10.3762/bjoc.11.159

Graphical Abstract
  • Differential scanning calorimetry (DSC) analysis of ring opening methatesis polymerization (ROMP) derived polydicyclopentadiene (PDCPD) revealed an unexpected thermal behavior. A recurring exothermic signal can be observed in the DSC analysis after an elapsed time period. This exothermic signal was found to be
  • of 98.9% at polymerization temperatures of 60 °C with the Grubbs first generation catalyst. By carrying out detailed differential scanning calorimetry (DSC) analyses Kessler and Mauldin [27] demonstrated a sharp exothermic peak related to the heat of reaction and a final Tg of 164 °C at conversions
  • of 90% right after curing. Dimonie et al. [28][29] examined the nature of the first exothermic peak of linear PDCPD using DSC and showed thermal polymerization completion after 2 h at 150 °C as the exothermic peak disappeared given these conditions. Kessler and White [30] also explored the cure
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Published 21 Aug 2015

Consequences of the electronic tuning of latent ruthenium-based olefin metathesis catalysts on their reactivity

  • Karolina Żukowska,
  • Eva Pump,
  • Aleksandra E. Pazio,
  • Krzysztof Woźniak,
  • Luigi Cavallo and
  • Christian Slugovc

Beilstein J. Org. Chem. 2015, 11, 1458–1468, doi:10.3762/bjoc.11.158

Graphical Abstract
  • reaction and responsible for the low(er) polymer yields and pronounced endothermic signals in the DSC traces (cf. Figure 9 right) [58]. While initiator 5a shows an appealing performance in polymerizing 23, the electronically modified congeners 14 and 15 are not particularly interesting for this application
  • . Big symbols: thermogravimetric analysis (TGA); no symbols: differential scanning calorimetry (DSC). trans–cis Isomerization. Synthesis of the ligand precursors. Synthesis of the ruthenium complexes. Possible reaction pathways of 16. Supporting Information Supporting Information File 360: Full
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Published 20 Aug 2015

Selected synthetic strategies to cyclophanes

  • Sambasivarao Kotha,
  • Mukesh E. Shirbhate and
  • Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

Graphical Abstract
  • synthesized hexa-peri-hexabenzocoronene cyclophane 201a–c. They studied their properties by carrying out differential scanning calorimetry (DSC), optical microscopy, wide-angle X-ray scattering (WAXD), and scanning tunneling microscopy (STM). Tunneling spectroscopy reveals a diode-like behavior which
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Published 29 Jul 2015

Synthesis of photoresponsive cholesterol-based azobenzene organogels: dependence on different spacer lengths

  • Yuchun Ren,
  • Bin Wang and
  • Xiuqing Zhang

Beilstein J. Org. Chem. 2015, 11, 1089–1095, doi:10.3762/bjoc.11.122

Graphical Abstract
  • designed and synthesized. The molecular structures were confirmed by 1H NMR and 13C NMR spectroscopy. The rapid and reversible photoresponsive properties of the compounds were investigated by UV–vis spectroscopy. Their thermal phase behaviors were studied by DSC. The length of the spacer plays a crucial
  • calorimetry (DSC). The DSC curves of the cholesterol-based supramolecular complexes are shown in Figure 2 and phase transition temperatures are listed in Table 1. The DSC thermogram of M0 presented three peaks at 158, 211 and 249 °C on heating, corresponding to the crystal to crystal transition, crystal to
  • mesophase transition and mesophase to isotropic transition. On the cooling run, DSC curves presented isotropic phase to mesophase, mesophase to crystal and crystal to crystal at 190, 155 and 126 °C. Each curve of compounds M2, M6 and M10 displayed a single endothermic melting peak. The heating DSC curves of
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Published 29 Jun 2015

Carboxylated dithiafulvenes and tetrathiafulvalene vinylogues: synthesis, electronic properties, and complexation with zinc ions

  • Yunfei Wang and
  • Yuming Zhao

Beilstein J. Org. Chem. 2015, 11, 957–965, doi:10.3762/bjoc.11.107

Graphical Abstract
  • of 9). It is therefore reasonable to propose that the microporosity in 8 is directly related to the coordination polymer structure. Finally, the thermal stability of coordination polymer 8 and Zn-DTF 9 were evaluated by differential scanning calorimetric (DSC) analysis, and detailed DSC traces are
  • illustrated in Figure 6. The DSC data of Zn-TTFV 8 (Figure 6A) manifested very good thermal stability up to 400 °C, without any significant melting or decomposition except a slight phase transition at 272 °C. Comparatively, the DSC trace of carboxyl-TTFV ligand 6 showed a distinctive melting process at 317 °C
  • significant exothermic peak at 358 °C (Figure 6C). For carboxyl-DTF 7, a notable melting point was observed at 199 °C, and the melting was followed by certain exothermic processes in the range of 200 to 285 °C. The DSC results indicated that the formation of Zn-TTFV coordinate polymer could give rise to
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Published 03 Jun 2015

Novel biphenyl-substituted 1,2,4-oxadiazole ferroelectric liquid crystals: synthesis and characterization

  • Mahabaleshwara Subrao,
  • Dakshina Murthy Potukuchi,
  • Girish Sharada Ramachandra,
  • Poornima Bhagavath,
  • Sangeetha G. Bhat and
  • Srinivasulu Maddasani

Beilstein J. Org. Chem. 2015, 11, 233–241, doi:10.3762/bjoc.11.26

Graphical Abstract
  • the compounds, i.e., the 13a (PhOx.C*Cn) and the 13b (C12.Ox.C*Cn) series are carried out by a Shimadzu (DSC-60) differential scanning calorimeter (DSC). The heating and cooling rates applied for the thermal studies are 10 °C/min. The thermograms of 13ap and 13bp are given in Figure 4 as
  • 13b (C12.Ox.C*Cn) are presented in Table 1 and Table 2, respectively. The phase diagrams are constructed with DSC cooling cycle data of the 13a (Ph.Ox.C*Cn) and the 13b (C12.Ox.C*Cn) series and are presented in Figure 5 and Figure 6, respectively. It is realized that the compounds of the 13a (Ph.Ox.C
  • fan texture exhibited by 13ar (Ph.Ox.C*C10) at 120 °C. (b) Broken focal conic fan texture exhibited by 13br (C12.Ox.C*C10) at 65 °C. Polarization profile of 13br (C12.Ox.C*C10) compound at 65 °C. Temperature dependant spontaneous polarisation in 13bp and 13br. DSC thermograms of 13ap and 13bp. Phase
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Published 11 Feb 2015

Inclusion of trans-resveratrol in methylated cyclodextrins: synthesis and solid-state structures

  • Lee Trollope,
  • Dyanne L. Cruickshank,
  • Terence Noonan,
  • Susan A. Bourne,
  • Milena Sorrenti,
  • Laura Catenacci and
  • Mino R. Caira

Beilstein J. Org. Chem. 2014, 10, 3136–3151, doi:10.3762/bjoc.10.331

Graphical Abstract
  • of the interaction between α-CD and RSV, for example, the disappearance of the melting endotherm for RSV in the differential scanning calorimetric (DSC) trace of the product was cited as evidence for the formation of a α-CD·RSV complex [9]. The putative inclusion complex between β-CD and RSV
  • co-crystallization from different solutions, by co-evaporation using a rotavapor, or by exposure to microwave radiation. Characterization of the products was achieved using DSC and simultaneous thermogravimetric analysis (TGA/DSC), with support from FTIR spectroscopy and PXRD, where necessary. An
  • prepare the binary systems. Differential scanning calorimetry (DSC) indicated that the commercial product melted at Tpeak,m = 266.3(4) °C (Tonset = 265.1(3) °C; ΔHm = 279(2) J g−1) (Figure 2, curve (a)). Thermogravimetric analysis (TGA) revealed mass loss only at 275 °C attributable to sample
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Published 29 Dec 2014

Modification of physical properties of poly(L-lactic acid) by addition of methyl-β-cyclodextrin

  • Toshiyuki Suzuki,
  • Ayaka Ei,
  • Yoshihisa Takada,
  • Hiroki Uehara,
  • Takeshi Yamanobe and
  • Keiko Takahashi

Beilstein J. Org. Chem. 2014, 10, 2997–3006, doi:10.3762/bjoc.10.318

Graphical Abstract
  • containing approximately 17% MeCD was drawn to more than 1000% at 60 °C, although PLLA fractured at a strain of less than 100%. Differential scanning calorimetry (DSC)-Raman in situ measurements also revealed decreases in the glass transition temperature (Tg), cold crystallization temperature (Tc), and
  • melting point (Tm), and improvement in structural distribution with temperature. DSC-Raman measurements simultaneously supplied information about crystallinity and thermal properties. Thus, it was concluded that MeCD had high affinity for PLLA, and the addition of MeCD increased the amorphous component of
  • PLLA and enhanced the drawability. Keywords: crystallinity; DSC; methyl-β-cyclodextrin; poly(L-lactic acid); Raman spectroscopy; Introduction Poly(L-lactic acid) (PLLA) has attracted attention because it is a biodegradable polymer derived from carbon-neutral resources. However, its melting point (Tm
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Published 16 Dec 2014

Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

  • Daniel I. Hădărugă,
  • Nicoleta G. Hădărugă,
  • Corina I. Costescu,
  • Ioan David and
  • Alexandra T. Gruia

Beilstein J. Org. Chem. 2014, 10, 2809–2820, doi:10.3762/bjoc.10.298

Graphical Abstract
  • formation was determined by thermal analysis (TG, DSC), FTIR and XRD. The quality of the encapsulation has been studied by gas chromatographic methods. Methylchavicol and other structurally related volatiles were also encapsulated in various natural CDs such as α- and β-CD, as well as in semisynthetic
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Published 28 Nov 2014

Synthesis and properties of novel star-shaped oligofluorene conjugated systems with BODIPY cores

  • Clara Orofino-Pena,
  • Diego Cortizo-Lacalle,
  • Joseph Cameron,
  • Muhammad T. Sajjad,
  • Pavlos P. Manousiadis,
  • Neil J. Findlay,
  • Alexander L. Kanibolotsky,
  • Dimali Amarasinghe,
  • Peter J. Skabara,
  • Tell Tuttle,
  • Graham A. Turnbull and
  • Ifor D. W. Samuel

Beilstein J. Org. Chem. 2014, 10, 2704–2714, doi:10.3762/bjoc.10.285

Graphical Abstract
  • molecular bromine which was used previously [33]. Thermal, electrochemical and optical properties TGA and DSC analyses All of the final target compounds showed good thermal stability. Thermogravimetric analysis (TGA) revealed decomposition temperatures in the range 396–442 °C (Table 1, Figure S1, Supporting
  • Information File 1). The morphological stability was evaluated by differential scanning calorimetry (DSC). All of the synthesised compounds were found to be amorphous materials and exhibited reasonably high glass transition temperatures (Tg) (Table 1, Figure S2, Supporting Information File 1). The Tg value
  • Perkin-Elmer Thermogravimetric Analyser TGA7 under a constant flow of argon. Differential Scanning Calorimetry (DSC) was conducted on a TA Instruments Q1000 with a RC-90 refrigerated cooling unit attached. The calibration was conducted using indium (melt temperature 156.42 °C, ∆Hf 28.42 J/g). The test
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Published 19 Nov 2014

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

  • Véronique Nardello-Rataj and
  • Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

Graphical Abstract
  • isotherms and in the solid state by thermal analysis (DSC) and X-ray diffractometry. The variation of the alkyl chain structure of the p-hydroxybenzoic acid esters revealed that the stability of the inclusion complexes was deeply modified (see binding constants in Table 3). As depicted in Table 3, the
  • problem of unstability of chloramine phosphate (chloramidophos, see Figure 3) as a pesticide by the formation of 1:1 inclusion complexes with β-CD [49]. The formation of inclusion complex was proved by DSC, Fourier transform infrared and X-ray diffraction [50]. The binding constant was estimated at 203 M
  • delivery applications [51]. The inclusion complexes were prepared by the freeze-drying method and characterized by transmission electronic microscopy, oxidative DSC and phase solubility. The encapsulation efficiency was very high for all the essential oils. The phase solubility method was typical of a 1:1
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Published 07 Nov 2014

Loose-fit polypseudorotaxanes constructed from γ-CDs and PHEMA-PPG-PEG-PPG-PHEMA

  • Tao Kong,
  • Lin Ye,
  • Ai-ying Zhang and
  • Zeng-guo Feng

Beilstein J. Org. Chem. 2014, 10, 2461–2469, doi:10.3762/bjoc.10.257

Graphical Abstract
  • -CDs to give rise to tight-fit double-chain stranded polypseudorotaxanes (PPRs). After attaching the PHEMA, the resulting pentablock copolymer was single-chain stranded into the interior of γ-CDs to form more stable, loose-fit PPRs. The results of 1H NMR, WXRD, DSC, TGA, 13C CP/MAS NMR and FTIR
  • with γ-CDs in aqueous solution to form PPRs. The results of 1H NMR, WXRD, DSC, TGA, 13C CP/MAS NMR and FTIR analyses indicate that the attachment of PHEMA clearly changes the self-assembly direction of γ-CDs with PHEMA-PPO-PEO-PPO-PHEMA. This results in unique, single-chain stranded, loose-fit PPRs
  • the decrease in conformational flexibility upon PPR formation. Furthermore, this indicates that a number of γ-CDs can still be held on the pentablock copolymer axle at a higher feed molar ratio, even in a highly polar DMSO solvent as previously described [25]. DSC measurements provide further evidence
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Published 23 Oct 2014

Oligomerization of optically active N-(4-hydroxyphenyl)mandelamide in the presence of β-cyclodextrin and the minor role of chirality

  • Helmut Ritter,
  • Antonia Stöhr and
  • Philippe Favresse

Beilstein J. Org. Chem. 2014, 10, 2361–2366, doi:10.3762/bjoc.10.246

Graphical Abstract
  • 500. MALDI–TOF spectra were performed on a Bruker Ultraflex TOF mass spectrometer, the molecular masses being recorded in linear mode. Dithranol was used as a matrix and sodium trifluoroacetate (NaTFA) as ionization reagent. The samples were dissolved in DMF. DSC measurements were performed using a
  • Mettler Toledo DSC 822. The GC–MS analyses were carried out on Thermo Finnigan Trace DSQ GC/MS-System with THF as solvent. HPLC analyses were performed on BioTek Konton 525 equipped with UV detector (at 260 nm, diode array detector HPLC 540) at room temperature (column: Chiralcel OD-H, eluent: methanol
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Published 10 Oct 2014

The effect of permodified cyclodextrins encapsulation on the photophysical properties of a polyfluorene with randomly distributed electron-donor and rotaxane electron-acceptor units

  • Aurica Farcas,
  • Ana-Maria Resmerita,
  • Pierre-Henri Aubert,
  • Flavian Farcas,
  • Iuliana Stoica and
  • Anton Airinei

Beilstein J. Org. Chem. 2014, 10, 2145–2156, doi:10.3762/bjoc.10.222

Graphical Abstract
  • -rotaxane sample, which hints at a different content of threaded TMS-β-CD or TMS-γ-CD on the copolymer chains (Table 1). The thermal properties of the copolymers were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results are summarized in Table 1. 4a and 4b
  • . Moreover, the decomposition temperature at 5% weight loss for TMS-γ-CD determined by TGA analysis is around 390 °C [32]. The DSC curves of the polyrotaxane samples showed glass-transitions temperature (Figure 5). The Tg values increase from 91 °C for 4 to 128 °C and 105 °C for 4a and 4b, respectively. The
  • DSC results suggest that the encapsulation of molecule 1 into TMS-β-CD and TMS-γ-CD cavities leads to more rigid copolymer structures with an increased Tg (Table 1). It should be pointed out that the higher molecular weight of 4a and 4b copolymers can also influence the phase transition temperature
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Published 09 Sep 2014

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

  • Alexander Burkhart and
  • Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1951–1958, doi:10.3762/bjoc.10.203

Graphical Abstract
  • measured at room temperature. FTIR spectra were recorded on a Nicolet 6700 FTIR spectrometer equipped with an ATR unit. Differential scanning calorimetry (DSC) was performed using a Mettler Toledo DSC 822 instrument equipped with a sample robot TSO801RO. For calibration, standard tin, indium, and zinc
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Published 21 Aug 2014

Copolymerization and terpolymerization of carbon dioxide/propylene oxide/phthalic anhydride using a (salen)Co(III) complex tethering four quaternary ammonium salts

  • Jong Yeob Jeon,
  • Seong Chan Eo,
  • Jobi Kodiyan Varghese and
  • Bun Yeoul Lee

Beilstein J. Org. Chem. 2014, 10, 1787–1795, doi:10.3762/bjoc.10.187

Graphical Abstract
  • using a Waters Millennium apparatus with polystyrene standards. The Tg data were determined from a second heating at a heating rate of 10 °C/min by differential scanning calorimetry (DSC) using a Thermal Analysis Q10 instrument. Typical procedure for PO/PA alternating copolymerizations. A bomb reactor
  • removed using a rotary evaporator, and the residual solvent was removed completely by keeping the isolated lump in a vacuum oven overnight at 100 °C. When the PA conversion was not 100%, the polymer was obtained admixed with unreacted PA. For DSC studies, small pieces of the polymer lump admixed with the
  • )CH2-carbonate; "c" signal for ester-CH2CH(Me)-carbonate; "d" signal for carbonate-CH2CH(Me)-carbonate; "*" signals for propylene carbonate; "#" signals for unreacted PA). GPC curves of the PO/PA copolymers. DSC curves of PO/PA alternating polymer (A, entry 1 in Table 1), PO/CO2/PA terpolymer (B, entry
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Published 05 Aug 2014
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