bluuebunny/crossref_metadata_2025 huggingface dataset:
Core‐shell ZrO2/PMMA composites via dispersion polymerization in supercritical fluid: Synthesis, characterization and mechanism
Authors: Haldorai Yuvaraj , Zong Tongqiang , Shim Jae‐Jin
Published: August 2011

Zirconia (ZrO2) particles of average size 200 nm were synthesized by sol–gel method and formation of composites with poly(methyl methacrylate) (PMMA) via in situ radical dispersion polymerization in supercritical carbon dioxide (scCO2) using a commercially available stabilizer poly(dimethylsiloxane)‐g‐pyrrolidone carboxylic acid (Monosil PCA). ZrO2 particles were first surface‐modified by the silane coupling agent methacryloxypropyltrimethoxysilane (MPTMS), which is capable of copolymerizing with methyl methacrylate (MMA) and provide a reactive CC bond. SEM results revealed uniform morphological characteristics of the composite materials and good dispersions of the ZrO2 particles. TEM analysis confirmed the core–shell morphology. The incorporation of ZrO2 particles in the composites was endorsed by FT‐IR. The composites were also confirmed by TGA and XRD. The hybrid composites possess interesting thermal and optical transparency characteristics because of the uniform incorporation of ZrO2 particles in the polymer matrix. In principle, this simple and environmentally friendly synthetic procedure can be employed to prepare other inorganic oxide containing polymer composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Electroluminescence properties of poly(3‐hexylthiophene)–cadmium sulfide nanoparticles grown in situ
Authors: Borriello C. , Masala S. , Bizzarro V. , Nenna G. , Re M. , Pesce E. , Minarini C. , Di Luccio T.
Published: August 2011

In this work, a simple approach to prepare luminescent poly(3‐hexylthiophene)–CdS nanocomposites to be employed in organic light emitting devices (OLED) devices is reported. The nucleation and growth of CdS nanoparticles were obtained by the thermolysis of a single Cd and S precursor dispersed in the polymer at three different temperatures of annealing: 240, 265, and 300°C. In this way, it was possible to compare the properties of nanocomposites containing nanoparticles with different sizes. X‐ray diffraction and transmission electron microscopy analyses confirmed the formation of CdS nanoparticles and gave information about the size, distribution, and morphology of the nanoparticles; monodispersive and very small nanoparticles with diameters below 2.5 nm were obtained at 240°C. The application of such nanocomposites as emitting layers in OLED devices is discussed. Enhanced electrooptical properties were observed for the device containing the nanocomposite annealed at 240°C with respect to the pure polymer based device. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Microstructuring of polymer films by inkjet etching
Authors: Grimaldi I. A. , De Girolamo Del Mauro A. , Nenna G. , Loffredo F. , Minarini C. , Villani F.
Published: August 2011

The inkjet printing (IJP) technique is generally used as tool for positioning small quantities of a liquid material on a target substrate. An interesting application of IJP is inkjet etching that consists of the deposition of drops of solvent or solvent mixtures onto a soluble polymer layer. This technique allows one to structure the polymer film and to change the shape, from concave to convex, by varying the mixing ratio of the solvents. In this work, the structuring of some polymeric layers (polyimide and polystyrene) by solvents [N‐methyl‐2‐pyrrolidone (NMP) and toluene (TOL)] and a solvent mixture (TOL–NMP) at different mixing ratios were studied, and the effect of the printing parameters on the microstructural profile was investigated. Some applications in optoelectronic devices are described. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Pore structure and swelling behavior of porous hydrogels prepared via a thermal reverse‐casting technique
Authors: Salerno Aurelio , Borzacchiello Rossella , Netti Paolo A.
Published: August 2011

In this work, we investigated the design and fabrication of porous polyacrylamide hydrogels via a thermal reverse‐casting technique. The porous hydrogels were prepared by the free‐radical crosslinking polymerization of the monomer solution within the space of an agarose gel, which after the setting of the chemical gel, was removed to allow for the formation of an interconnected porosity pathway. Two different agarose/monomer solution ratios were selected to modulate the porosity of the hydrogels, and the as‐obtained samples were characterized in terms of their chemical structure, morphology, thermal properties, and swelling behavior in different ionic strength solutions. The results of this study demonstrate that the reverse‐casting process enhanced the solvent‐retaining capability of the hydrogels and that their swelling ratio increased with increasing concentration of the agarose solution in the initial formulation. All of these results finally demonstrate that the pore structure features played a key role in defining the swelling behavior of the hydrogels. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of diisocyanate structure on the properties and microstructure of polyurethanes based on polyols derived from renewable resources
Authors: Corcuera Ma. Angeles , Rueda Lorena , Saralegui Ainara , Martín Ma. Dolores , Fernández‐d'Arlas Borja , Mondragon Iñaki , Eceiza Arantxa
Published: August 2011

Polyols derived from renewable resources are good candidates for obtaining segmented polyurethane (PU) elastomers. Diisocyanates with different chemical structures, aliphatic and aromatic, were used to synthesize PU elastomers with different hard‐segment (HS) contents by a two‐step polymerization procedure. Microphase separation and thermal stability were studied with attenuated total reflection Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. The analysis of H‐bonded and non‐H‐bonded urethane carbonyl stretching vibration in the amide I region, the glass‐transition temperatures of the soft segments and HSs, and the melting temperature and enthalpies of the HSs revealed that aliphatic diisocyanate based PUs presented a higher phase separation degree and higher HS crystallinity and also a superior thermal stability to the aromatic diisocyanate‐based PUs. The aromatic diisocyanate‐based PU presented a higher ductility, higher tensile strength, and lower modulus than aliphatic diisocyanate‐based PU for the same HS content because of the different morphology that they presented. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation, characterization, and release behavior of nanocomposite microparticles based on polystyrene and different layered silicates
Authors: Scarfato Paola , Russo Pietro , Acierno Domenico
Published: August 2011

A microparticulated, organic–inorganic hybrid system, useful as an active agent carrier, was successfully developed with an emulsification/solvent evaporation method. The system consisted of nanostructured polystyrene microparticles containing different silicates as nanosized fillers and benzophenone (BP) as a model active substance. The adopted preparation procedure gave high yields of microparticles, which displayed regular geometry and high encapsulation efficiency of the active agent. X‐ray diffraction measurements showed that all of the hybrid systems had a polymer–silicate intercalated morphology and the BP was molecularly dispersed in the microspheres. Moreover, preliminary in vitro release tests evidenced that the inclusion of the nanodispersed silicates into the polymer matrix significantly modified the release behavior of BP, depending on the silicate type. Therefore, the nanocomposite microparticles are of great potential in the field of controlled release. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Altering the onset of cocontinuity in nanocomposite immiscible blends by acting on the melt‐compounding procedure
Authors: Filippone G. , Acierno D.
Published: August 2011

The addition of nanoparticles to polymer systems with an existing phase‐separated morphology, such as polymer blends, represents an innovative approach to controlling the microstructure and, hence, the macroscopic properties of the material. During the melt mixing of the constituents, the particles migrate toward specific regions of the material and are driven by more favorable thermodynamic interactions. Kinetic effects related to the high viscosity of the polymer melts, however, may lead to nonequilibrium morphologies. This makes the mixing procedure crucial for controlling the space distribution of the filler and, hence, the microstructure of the blend and its final properties. We focused on this topic by investigating the effect of the sequence of addition of the constituents in blends of polystyrene and polyamide 6 filled with an organoclay prepared by melt compounding. We show that the mixing procedure could bring about alterations in the onset of cocontinuity, which could be exploited to enhance the high‐temperature mechanical strength of the blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Measurement of the interfacial attraction between graphene oxide sheets and the polymer in a nanocomposite
Authors: Kranbuehl D. E. , Cai M. , Glover A. J. , Schniepp H. C.
Published: August 2011

The objective of this work was to characterize and, thereby, achieve a fundamental scientific understanding at the molecular level of the relationship of the intermolecular forces measured at the nanoscale between an individual nanoparticle and a polymer. In this study, we developed a method to directly characterize and measure the relative strength of the interfacial attractive forces between graphene oxide (GO) nanoparticles and the polymer matrix on the nanoscale using atomic force microscopy techniques to evaluate individual particles. The method was successfully applied to study the interfacial attractive forces in GO–polymer nanocomposites. Two polymers [poly(methyl methacrylate) and poly(vinyl alcohol)] were studied. The results support that this method is capable of characterizing the interfacial attractive forces directly at the nanoscale. The method can be applied to other nanoparticle–macromolecular systems, allowing the determination of the interaction strength between nanoparticles and the macromolecular material. This information paves the way to characterize the relationship between interfacial forces at the nanometer level to a nanocomposite's performance properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Modeling of the isobaric and isothermal glass transitions of polystyrene
Authors: Grassia Luigi , Carbone Maria Giovanna Pastore , D'Amore Alberto
Published: August 2011

The scaling law for relaxation times (τ's) recently proposed by Casalini and Roland was used in the framework of Kovacs, Aklonis, Hutchinson, and Ramos phenomenological theory. With this approach, it was shown that both the isobaric and the isothermal glass transitions of polystyrene can be reliably predicted with only two fitting parameters, namely, τ in the reference state and the fractional exponent that describes the dispersion of the α relaxation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Silicone‐rubber‐based tactile sensors for the measurement of normal and tangential components of the contact force
Authors: D'Amore Alberto , De Maria Giuseppe , Grassia Luigi , Natale Ciro , Pirozzi Salvatore
Published: August 2011

This article presents the developmental process of a new tactile sensor. The sensor was based on the use of light‐emitting diode (LED) phototransistor couples and a silicone rubber layer positioned above the optoelectronics devices. The optoelectronic components were organized in a matrix structure. For each couple, the LED illuminated the reflective surface, which coincided with the bottom facet of the deformable layer. Practically, the deformable layer transduced an external force into a displacement variation of its bottom facet through its stiffness. An external force applied to the deformable layer produced local variations of the bottom surface of the elastic material, and the couples of optical devices measured the vertical deformations in a discrete number of points. In particular, these vertical displacements produced a variation of the reflected light intensity and, accordingly, of the photocurrent measured by the photodetector. The realized prototype was designed and optimized through finite element analysis. A calibration procedure is also presented, whose results demonstrate the ability of the sensor to reconstruct the contact point and also the normal and tangential components of the contact force. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Determination of the molecular states of the processive endocellulase Thermobifida fusca Cel9A during crystalline cellulose depolymerization
Authors: Kostylev Maxim , Moran‐Mirabal Jose M. , Walker Larry P. , Wilson David B.
Published: August 2011

Detailed understanding of cell wall degrading enzymes is important for their modeling and industrial applications, including in the production of biofuels. Here we used Cel9A, a processive endocellulase from Thermobifida fusca, to demonstrate that cellulases that contain a catalytic domain (CD) attached to a cellulose binding module (CBM) by a flexible linker exist in three distinct molecular states. By measuring the ability of a soluble competitor to reduce Cel9A activity on an insoluble substrate, we show that the most common state of Cel9A is bound via its CBM, but with its CD unoccupied by the insoluble substrate. These findings are relevant for kinetic modeling and microscopy studies of modular glycoside hydrolases. Biotechnol. Bioeng. 2012;109: 295–299. © 2011 Wiley Periodicals, Inc.
Cation exchange chromatography provides effective retrovirus clearance for antibody purification processes
Authors: Connell‐Crowley Lisa , Nguyen Thao , Bach Julia , Chinniah Shivanthi , Bashiri Houman , Gillespie Ron , Moscariello John , Hinckley Peter , Dehghani Houman , Vunnum Suresh , Vedantham Ganesh
Published: August 2011

One measure taken to ensure safety of biotherapeutics produced in mammalian cells is to demonstrate the clearance of potential viral contaminants by downstream purification processes. This paper provides evidence that cation exchange chromatography (CEX), a widely used polishing step for monoclonal antibody (mAb) production, can effectively and reproducibly remove xMuLV, a retrovirus used as a model of non‐infectious retrovirus‐like particles found in Chinese hamster ovary cells. The dominant mechanism for xMuLV clearance by the strong cation exchanger, Fractogel SO, is by retention of the virus via adsorption instead of inactivation. Experimental data defining the design space for effective xMuLV removal by Fractogel SO with respect to operational pH, elution ionic strength, loading, and load/equilibration buffer ionic strength are provided. Additionally, xMuLV is able to bind to other CEX resins, such as Fractogel COO− and SP Sepharose Fast Flow, suggesting that this phenomenon is not restricted to one type of CEX resin. Taken together, the data indicate that CEX chromatography can be a robust and reproducible removal step for the model retrovirus xMuLV. Biotechnol. Bioeng. 2012;109: 157–165. © 2011 Wiley Periodicals, Inc.
Cultural Threat and Anti‐immigrant Prejudice: The Case of Protestants in Northern Ireland
Authors: Pehrson Samuel , Gheorghiu Mirona A. , Ireland Tomas
Published: August 2011

Cultural threat has emerged as a consistent predictor of anti‐immigrant and anti‐minority attitudes across many different national contexts. We examine this issue in the context of Northern Ireland using representative survey data, suggesting that Protestant and unionist communities experience a higher level of cultural threat than Catholic and nationalist communities on account of the ‘parity of esteem’ principle that has informed changes in the province since the Belfast Agreement of 1998. Our analyses confirm that, although there is evidence for some level of anti‐immigrant sentiment across all groups, Protestants and unionists do indeed report relatively more negative attitudes towards a range of immigrant and ethnic target groups compared with Catholics, nationalists or respondents who do not identify with any political category. The analyses further suggest that their higher level of perceived cultural threat partially accounts for this difference. We argue that cultural threat can be interpreted as a response to changes in Northern Ireland that have challenged the dominant status enjoyed by Protestants and unionists in the past. More generally, we argue that a politicised characterisation of cultural threat needs to be elaborated through future work. Copyright © 2011 John Wiley & Sons, Ltd.
The effects of hypercaloric diets on glucose homeostasis in the rat: influence of saturated and monounsaturated dietary lipids
Authors: Hoefel A. L. , Hansen F. , Rosa P. D. , de Assis A. M. , da Silveira S. L. , Denardin C. C. , Pettenuzzo L. , Augusti P. R. , Somacal S. , Emanuelli T. , Perry M. L. S. , Wannmacher C. M. D.
Published: August 2011

Consumption of energy‐dense/high‐fat diets is strongly and positively associated with overweight and obesity, which are associated with increase in the prevalence of certain chronic diseases. We evaluated the effect of hypercaloric/fat or normocaloric diets on some biochemical parameters in rats. Seventy‐two rats were divided into four groups that were fed for 16 weeks with diets: normocaloric [9.12% soy oil, normocaloric soy oil (NSO)], hypercaloric olive oil [43.8% olive oil, hypercaloric olive oil (HOO)], hypercaloric saturated fat [43.8% saturated fat, hypercaloric saturated fat (HSF)] and normocaloric saturated fat [43.8% saturated fat, normocaloric saturated fat (NSF)]. HSF rats consumed more calories daily than the others and gained more retroperitoneal fat, although HSF and HOO rats had higher body weight. In liver, glycogen synthesis and concentration were higher in rats HSF and NSF. In plasma, total cholesterol (TC) levels were higher in HSF rats than in the others, and triacylglycerol (TAG) levels were lower in HOO and higher in HSF rats in relation to the others. In liver, TC and TAG were elevated in HSF, NSF and HOO rats. Paraoxonase 1 activity, which is related to high‐density lipoprotein cholesterol and has anti‐atherogenic role was lower in rats HSF. In HOO rats, glucose tolerance test was altered, but insulin tolerance test was normal. These results suggest that consumption of energy‐dense/high‐fat diets, both saturated or monounsaturated, causes damaging effects. However, more studies are necessary to understand the mechanisms by which these diets cause the metabolic alterations observed. Copyright © 2011 John Wiley & Sons, Ltd.
The Role of the Counterion and of Silicon Chelation in the Selective Mono(trifluoromethylation) of Tartaric Acid Derived 1,4‐Diketones
Authors: Harakat Dominique , Massicot Fabien , Nonnenmacher Jean , Grellepois Fabienne , Portella Charles
Published: August 2011

The addition of trifluoromethyl(trimethyl)silane (TFMTMS) to tartaric acid derived aromatic 1,4‐diketones was reported to be highly stereoselective but also chemoselective towards a monoaddition product. This chemoselectivity remained unexplained. Complementary experiments and monitoring of the reaction by electrospray ionization mass spectrometry (ESI‐MS) show that: i) the countercation (tetrabutylammonium (TBA+) or Cs+) associated to the initiator and the charged intermediates in the chain reaction plays a crucial role and ii) in the case of a tetrabutylammonium salt initiator, the second addition on the preformed monoadduct does occur but the resulting bis(trifluoromethyl)carbinolate is unable to evolve through the chain‐transfer process and it exhibits an intramolecular SiO interaction.
Relating Structural Aspects of Bimetallic Pt3Cr1/C Nanoparticles to Their Electrocatalytic Activity, Stability, and Selectivity in the Oxygen Reduction Reaction
Authors: Taufany Fadlilatul , Pan Chun‐Jern , Chou Hung‐Lung , Rick John , Chen Yong‐Siou , Liu Din‐Goa , Lee Jyh‐Fu , Tang Mau‐Tsu , Hwang Bing‐Joe
Published: August 2011

Two methods were used to prepare bimetallic Pt3Cr1/C nanocatalysts with similar composition but different alloying extent (structure). We investigated how these differences in alloying extent affect the catalytic activity, stability and selectivity in the oxygen reduction reaction (ORR). One method, based on slow thermal decomposition of the Cr precursor at a rate that matches that of chemical reduction of the Pt precursor, allows fine control of the composition of the Pt3Cr1/C alloy, whereas the second approach, using the ethylene glycol method, results in considerable deviation (>25 %) from the projected composition. Consequently, these two methods lead to variations in the alloying extent that strongly influence the Pt d‐band vacancy and the Pt electroactive surface area (Pt ESCA). This relationship was systematically evaluated by transmission electron microscopy, X‐ray absorption near edge structure spectroscopy, and electrochemical analysis. The ORR activity depends on two effects that nullify each other, namely, the number of active Pt sites and their activity. The Pt‐site activity is more dominant in governing the ORR activity. The selectivity of the nanocatalyst towards the ORR and the competitive methanol oxidation reaction (MOR) depend on these two effects acting in cooperation to give enhanced ORR activity with suppressed MOR. The number of active Pt sites is associated with the Pt ESCA value, while Pt‐site activity is associated with the alloying extent and Pt d‐band vacancy (electronic) effects. The presence of Cr atoms in Pt3Cr1/C enhances stability during electrochemical treatment. Overall, the Pt3Cr1/C catalyst prepared by controlled‐composition synthesis was shown to be superior in ORR activity, selectivity and stability owing to its favorable alloying extent, Pt d‐band vacancy, and Pt ESCA.
New Light on the Ring–Chain Equilibrium of a Hydrogen‐Bonded Supramolecular Polymer Based on a Photochromic Dithienylethene Unit and its Energy‐Transfer Properties as a Storage Material
Authors: Li Shao‐Lu , Xiao Tangxin , Xia Wei , Ding Xia , Yu Yihua , Jiang Juli , Wang Leyong
Published: August 2011

A novel, bifunctional, quadruple hydrogen‐bonding ureido‐pyrimidinone (UPy) unit bridged by photochromic dithienylethene (1) has been synthesized, which affords linear assemblies in solution and undergoes concentration‐dependent ring‐opening polymerization. The two UPy functional groups of 1 can dimerize intramolecularly to form a cyclic monomer with the two thienyl rings fixed in a parallel conformation, which prohibits its photocyclization. We exploited the photochemical reactivity and resonance difference of the linker of the bis‐UPy derivative as well as using the more typical 1H NMR, DOSY, and Ubbelohde viscometry methods to investigate for the first time the ring–chain polymerization mechanism. Moreover, we fabricated a mixed polymer film with a fluorescent dye noncovalently endcapping the linear photochromic assemblies through quadruple hydrogen bonds, which showed nondestructive fluorescent read‐out ability for data storage by fluorescence resonance energy transfer (FRET) from the fluorescent dye to the closed form of the diarylethene.
Graphene Sheet/Porous NiO Hybrid Film for Supercapacitor Applications
Authors: Xia Xinhui , Tu Jiangping , Mai Yongjin , Chen Rong , Wang Xiuli , Gu Changdong , Zhao Xinbing
Published: August 2011

We report the preparation of a nickel‐foam‐supported graphene sheet/porous NiO hybrid film by the combination of electrophoretic deposition and chemical‐bath deposition. The obtained graphene‐sheet film of about 19 layers was used as the nanoscale substrate for the formation of a highly porous NiO film made up of interconnected NiO flakes with a thickness of 10–20 nm. The graphene sheet/porous NiO hybrid film exhibits excellent pseudocapacitive behavior with pseudocapacitances of 400 and 324 F g−1 at 2 and 40 A g−1, respectively, which is higher than those of the porous NiO film (279 and 188 F g−1 at 2 and 40 A g−1). The enhancement of the pseudocapacitive properties is due to reinforcement of the electrochemical activity of the graphene‐sheet film.
Redox Non‐Innocence of Thioether Crowns: Spectroelectrochemistry and Electronic Structure of Formal Nickel(III) Complexes of Aza–Thioether Macrocycles
Authors: Stephen Emma , Huang Deguang , Shaw Jennifer L. , Blake Alexander J. , Collison David , Davies E. Stephen , Edge Ruth , Howard Judith A. K. , McInnes Eric J. L. , Wilson Claire , Wolowska Joanna , McMaster Jonathan , Schröder Martin
Published: August 2011

The NiII complexes [Ni([9]aneNS2‐CH3)2]2+ ([9]aneNS2‐CH3=N‐methyl‐1‐aza‐4,7‐dithiacyclononane), [Ni(bis[9]aneNS2‐C2H4)]2+ (bis[9]aneNS2‐C2H4=1,2‐bis‐(1‐aza‐4,7‐dithiacyclononylethane) and [Ni([9]aneS3)2]2+ ([9]aneS3=1,4,7‐trithiacyclononane) have been prepared and can be electrochemically and chemically oxidized to give the formal NiIII products, which have been characterized by X‐ray crystallography, UV/Vis and multi‐frequency EPR spectroscopy. The single‐crystal X‐ray structure of [NiIII([9]aneNS2‐CH3)2](ClO4)6⋅(H5O2)3 reveals an octahedral co‐ordination at the Ni centre, while the crystal structure of [NiIII(bis[9]aneNS2‐C2H4)](ClO4)6⋅(H3O)3⋅ 3H2O exhibits a more distorted co‐ordination. In the homoleptic analogue, [NiIII([9]aneS3)2](ClO4)3, structurally characterized at 30 K, the NiS distances [2.249(6), 2.251(5) and 2.437(2) Å] are consistent with a Jahn–Teller distorted octahedral stereochemistry. [Ni([9]aneNS2‐CH3)2](PF6)2 shows a one‐electron oxidation process in MeCN (0.2 M NBu4PF6, 293 K) at E1/2=+1.10 V versus Fc+/Fc assigned to a formal NiIII/NiII couple. [Ni(bis[9]aneNS2‐C2H4)](PF6)2 exhibits a one‐electron oxidation process at E1/2=+0.98 V and a reduction process at E1/2=−1.25 V assigned to NiII/NiIII and NiII/NiI couples, respectively. The multi‐frequency X‐, L‐, S‐, K‐band EPR spectra of the 3+ cations and their 86.2 % 61Ni‐enriched analogues were simulated. Treatment of the spin Hamiltonian parameters by perturbation theory reveals that the SOMO has 50.6 %, 42.8 % and 37.2 % Ni character in [Ni([9]aneNS2‐CH3)2]3+, [Ni(bis[9]aneNS2‐C2H4)]3+ and [Ni([9]aneS3)2]3+, respectively, consistent with DFT calculations, and reflecting delocalisation of charge onto the S‐thioether centres. EPR spectra for [61Ni([9]aneS3)2]3+ are consistent with a dynamic Jahn–Teller distortion in this compound.
The Conversion of Furans into Phosphinines
Authors: Mao Yanli , Mathey François
Published: August 2011

The [4+2] cycloadducts between furan compounds and a methylenechlorophosphane pentacarbonyltungsten complex are converted into the corresponding 2‐hydroxy‐ or 2‐bromophosphinine complexes by treatment with BBr3 and triethylamine. The X‐ray crystal structure of the parent 2‐phosphaphenol complex shows that the hydroxy substituent is coplanar with the ring and that the conjugation between the π lone pair of electrons on the oxygen atom and the ring leads to lengthening of the PC(OH) bond. This complex is methylated at the phosphorus atom by methyl iodide with disruption of the ring aromaticity. The complex is further silylated, acylated, and triflated at the oxygen atom with retention of the aromatic structure, and decomplexation by 1,2‐bis(diphenylphosphino)propane (DPPE) leads to the free parent 2‐phosphaphenol. The comparison of the X‐ray crystallographic structural analysis of the 2‐bromophosphinine complex with an earlier structure of the analogous 2‐chlorophosphinine complex suggests that 2‐bromo species is a better ligand than 2‐chlorophosphinine. When the [4+2] adducts are treated with BBr3 and water, a 2‐hydroxy‐3‐bromo‐1,2,3,6‐tetrahydrophosphinine derivative is obtained, which yields a seven‐membered 2,1‐phosphaoxepin when treated with an amine.
Multifunctional Manganese Carbonate Microspheres with Superparamagnetic and Fluorescent Properties: Synthesis and Biological Application
Authors: Peng Juan , Feng Li‐Na , Zhang Kui , Li Jing‐Jing , Jiang Li‐Ping , Zhu Jun‐Jie
Published: August 2011

Multifunctional manganese carbonate microspheres with superparamagnetic and fluorescent properties were fabricated and used as biological labels. The Fe3O4@MnCO3 microspheres were synthesized by direct co‐precipitation without any linker shell. The Fe3O4@MnCO3 microspheres have uniform size distribution and rough surface, which provides a promising template for the assembly of polyelectrolytes (PEs) and CdTe quantum dots (QDs). A luminescent CdTe shell was observed in Fe3O4@MnCO3@PE‐CdTe spheres by confocal fluorescence imaging. With excellent solubility in water and rough surfaces, the multifunctional microsphere offers a friendly microenvironment for immobilization of α‐fetoprotein (AFP) antibodies (Ab2) to fabricate Fe3O4@MnCO3@PE‐CdTe‐Ab2 architecture. By using the Fe3O4@MnCO3@PEs‐CdTe‐Ab2 bioconjugate as a label, a promising and versatile platform for fluorescence imaging and electrochemical immunosensing of cancer biomarker AFP was developed. The prepared electrochemical immunosensor shows high sensitivity and selectivity with a detection limit of 0.3 pg mL−1.
Layer‐by‐Layer Assembly of Na9[EuW10O36]⋅32 H2O and Layered Double Hydroxides Leading to Ordered Ultra‐Thin Films: Cooperative Effect and Orientation Effect
Authors: Xu Junhua , Zhao Shen , Han Zhenzhen , Wang Xiaoting , Song Yu‐Fei
Published: August 2011

Well‐ordered, ultra‐thin films (UTFs) based on the hybrid assembly of Na9[EuW10O36]⋅32 H2O (denoted as EuW10) and exfoliated MgAl layered double hydroxide (LDH) monolayers have been fabricated by utilising a layer‐by‐layer (LBL) technique. The assembly process was monitored by UV/Vis absorption and fluorescence spectroscopy measurements to get a stepwise and regular growth of the UTFs upon increasing the deposited cycles. In the resulting (EuW10/LDH)n UTFs, the intercalation of EuW10 anions into LDH monolayers allows the UTFs to retain their optical properties. Meanwhile, LDH monolayers provide EuW10 with a confined and protective microenvironment to isolate them from each other between adjacent layers. The UTFs exhibit a periodic, long‐range, ordered structure. Anisotropic luminescence spectroscopy measurements show that the (EuW10/LDHs)n UTFs display well‐defined red luminescence with an anisotropy value, r, of about 0.15. Therefore, the cooperative and orientation effects between the host layers and guest anions play significant roles for the improved properties of the (EuW10/LDHs)n UTFs. This work could benefit the design and fabrication of novel electro‐optical devices based on the UTFs of hybrid materials.
Dynamics of Closure of Zinc Bis‐Porphyrin Molecular Tweezers with Copper(II) Ions and Electron Transfer
Authors: Habermeyer Benoit , Takai Atsuro , Gros Claude P. , El Ojaimi Maya , Barbe Jean‐Michel , Fukuzumi Shunichi
Published: August 2011

Zinc bis‐porphyrin molecular tweezers composed of a N4 spacer bound through pyridyl units to the meso position of porphyrins were synthesized, and the tweezers are closed by the coordination of a copper(II) ion inside the spacer ligand. The effect of the π–π interaction between the porphyrin rings in the closed conformation on the absorption spectra of multi‐electron oxidized species and the reduction potentials were clarified by chemical and electrochemical oxidation of the closed form of the zinc bis‐porphyrin molecular tweezers in comparison with the open form without copper(II) ion and the corresponding porphyrin monomer. The shifts in redox potentials and absorption spectrum of the porphyrin dication indicate a strong electronic interaction between the two oxidized porphyrins in the closed form, whereas there is little interaction between them in the neutral form. The dynamics of copper(II) ion coordination and subsequent electron transfer was examined by using a stopped‐flow UV/Vis spectroscopic technique. It was confirmed that coordination of copper(II) occurs prior to electron‐transfer oxidation of the closed form of the zinc bis‐porphyrin molecular tweezers.
Supramolecular Isomerism of 2,2′‐Bipyrazine Complexes with cis‐(NH3)2PtII: Ligand Rotational State and Sequential Orientation Determine the 3D Shape of Metallacycles
Authors: Galstyan Anzhela , Shen Wei‐Zheng , Freisinger Eva , Alkam Hussein , Hiller Wolf , Sanz Miguel Pablo J. , Schürmann Markus , Lippert Bernhard
Published: August 2011

2,2′‐Bipyrazine (2,2′‐bpz) reacts with cis‐(NH3)2PtII in water to give a variety of products, several of which were isolated and characterized by X‐ray analysis: cis‐[Pt(NH3)2(2,2′‐bpz‐N4)2](NO3)2⋅3 H2O (1), [{cis‐Pt(NH3)2(2,2′‐bpz‐N4,N4′)}3](PF6)5NO3⋅7 H2O (2 a), [{cis‐Pt(NH3)2(2,2′‐bpz‐N4,N4′)}3](BF4)2(SiF6)2⋅15 H2O (2 b), and [{cis‐Pt(NH3)2(2,2′‐bpz‐N4,N4′)}4](SO4)4⋅22 H2O (3). In 1, 2 b, and 3 the 2,2′‐bpz ligands adopt approximately C2h symmetries, hence the two pyrazine halves are in trans orientation, whereas in 2 a all three 2,2′‐bpz bridges are approximately C2v symmetric, with the pyrazine halves cis to each other. The topologies of the two triangular complexes 2 a and 2 b are consequently distinctly different, but nevertheless both cations act as hosts for anions. In 2 a a PF6− and a NO3− anion are associated simultaneously with the +6 cation, whereas in 2 b it is a BF4− anion and a water molecule, which are trapped in its cavity. There is no anion inclusion in case of the metallasquare 3. In principle, 3 can exist in a large number of stereoisomers, depending on the rotational states of the bridging 2,2′‐bpz ligands. Isolation of a single rotamer form of 3 with C2h symmetric 2,2′‐bpz ligands and an overall meso form is proposed to be a consequence of a highly efficient self‐assembly process that starts from the precursor 1 and reaction with two cis‐(NH3)2PtII units. This process leads to the isolated rotamer of 3 regardless of whether two cations 1 in head–head form react with two cis‐(NH3)2PtII, or whether the Δ enantiomer of the chiral head–tail form of 1 combines with its Λ enantiomer through two cis‐(NH3)2PtII entities.
The Structure of Water in p‐Sulfonatocalix[4]arene
Authors: Fucke Katharina , Anderson Kirsty M. , Filby Maria H. , Henry Marc , Wright Jonathan , Mason Sax A. , Gutmann Matthias J. , Barbour Leonard J. , Oliver Clive , Coleman Anthony W. , Atwood Jerry L. , Howard Judith A. K. , Steed Jonathan W.
Published: August 2011

Tetrasodium p‐sulfonatocalix[4]arene exists as a hydrate with approximately 14 water molecules and has three polymorphic modifications, all of which contain a water molecule in the molecular cavity that is engaged in OH⋅⋅⋅π interactions. Single‐crystal neutron structures are reported for two of these three forms and reveal a “compressed” water molecule with short OH bonds. Partial atomic charges and hardness analysis (PACHA) calculations based on the neutron coordinates give an OH⋅⋅⋅π interaction energy of 6.9–7.5 kJ mol−1. The PACHA analysis also reveals the dominance of the charge‐assisted hydrogen bonds from the Na+‐coordinated water molecules. The instability of the crystal towards dehydration can be traced to an uncoordinated lattice water site. The remarkable calixarene‐Na+‐hydrate motif is conserved almost unchanged across all three polymorphs. A single‐crystal neutron structure is also reported for pentasodium p‐sulfonatocalix[4]arene⋅12 H2O, which exhibits an intracavity water molecule that is engaged in both OH⋅⋅⋅π and OH⋅⋅⋅O hydrogen bonding. The shorter covalent bond to the hydrogen atom that forms the interaction with the aromatic ring is again apparent.
ChemInform Abstract: Refined Crystal Structure and Idealized Structure of Mixed‐Valent Eu4F5(CN2)2: Transition Possible.
Authors: Unverfehrt Leonid , Stroebele Markus , Glaser Jochen , Langer Thorsten , Hoffmann Rolf‐Dieter , Poettgen Rainer , Meyer H.‐Juergen
Published: August 2011

The title compound is prepared by solid state reaction of EuF3, EuF2+x, and Li2(CN2) at 700 °C and characterized by single crystal XRD, 151Eu Moessbauer spectroscopy, and magnetic measurements.
ChemInform Abstract: Scaffolding, Ladders, Chains, and Rare Ferrimagnetism in Intermetallic Borides: Synthesis, Crystal Chemistry and Magnetism.
Authors: Goerens Christian , Brgoch Jakoah , Miller Gordon J. , Fokwa Boniface P. T.
Published: August 2011

The new complex boride phases Ti8Fe3Ru18B8 and Ti7Fe4Ru18B8 are synthesized by arc‐melting of the elements.
ChemInform Abstract: “Chemical Metamagnetism”: From Antiferromagnetic PrCo2P2 to Ferromagnetic Pr0.8Eu0.2Co2P2 via Chemical Compression.
Authors: Kovnir Kirill , Reiff William M. , Menushenkov Alexey P. , Yaroslavtsev Alexander A. , Chernikov Roman V. , Shatruk Michael
Published: August 2011

Pr0.8M0.2Co2P2 (M: Eu, Ca) are synthesized from mixtures of the elements in a Sn flux (silica ampules, 1155 K, 10 d) and characterized by powder and single crystal XRD, Moessbauer spectroscopy, magnetic measurements, and DFT band structure calculations.
ChemInform Abstract: Formation and Properties of SrB6 Single Crystals Synthesized under High Pressure and Temperature.
Authors: Yu Dongli , et al. et al.
Published: August 2011

SrB6 single crystals are grown from Sr pellets and B powder at 5 GPa and 1300 °C (3 h).
ChemInform Abstract: 1,1,1‐Tris(distanna‐closo‐dodecaborate)stannate: A Tripodal Tin Ligand.
Authors: Nickl Claudia , Eichele Klaus , Joosten Dominik , Langer Thorsten , Schappacher Falko M. , Poettgen Rainer , Englert Ulli , Wesemann Lars
Published: August 2011

The unprecedented [Sn(Sn2B10H10)3]4‐ anion of (III) with a Sn7 skeleton forms a tripodal coordination socket.
ChemInform Abstract: Two New Neptunyl(V) Selenites: A Novel Cation—Cation Interaction Framework in (NpO2)3(OH)(SeO3) (H2O)2·H2O and a Uranophane‐Type Sheet in Na(NpO2)(SeO3)(H2O).
Authors: Jin Geng Bang , Skanthakumar S. , Soderholm L.
Published: August 2011

The structures of the new compounds (III) and (V) are determined by single crystal XRD.
ChemInform Abstract: A Reversal Phenomenon of Enantioface Selectivity by the Cooperative Operation of Two Chiral Catalyst.
Authors: Kawasaki Tsuneomi , Wakushima Yuki , Asahina Mai , Shiozawa Kazuya , Kinoshita Tomoyuki , Lutz Francois , Soai Kenso
Published: August 2011

The reversal phenomenon of enantioface selectivity in the asymmetric addition of diisopropylzinc (II) to aromatic aldehydes (I) and (IV) is observed by mixing two chiral β‐amino alcohol catalysts.
ChemInform Abstract: Catalytic Asymmetric Chloroamination Reaction of α,β‐Unsaturated γ‐Keto Esters and Chalcones.
Authors: Cai Yunfei , Liu Xiaohua , Jiang Jun , Chen Weiliang , Lin Lili , Feng Xiaoming
Published: August 2011

The title reaction is performed with a 1:1 mixture of TosNCl2 and TosNH2 which makes the chloroamination highly efficient.
ChemInform Abstract: Direct Catalytic Asymmetric Aminoallylation of Aldehydes: Synergism of Chiral and Nonchiral Broensted Acids.
Authors: Ren Hong , Wulff William D.
Published: August 2011

The combination of axially chiral boroxinate BNB and benzoic acid catalyzes the aminoallylation of aromatic or aliphatic aldehydes with amine (II) to give the resulting homoallylic amines in analytically pure form without application of chromatography.
ChemInform Abstract: Phosphine‐Catalyzed β′‐Umpolung Addition of Nucleophiles to Activated α‐Alkyl Allenes.
Authors: Martin Tioga J. , Vakhshori Venus G. , Tran Yang S. , Kwon Ohyun
Published: August 2011

First examples of β′‐umpolung addition of O‐, N‐, S‐, and C‐nucleophiles to activated α‐alkyl allenes are reported.
ChemInform Abstract: Polyethylene Glycol Clicked Co(II) Schiff Base and Its Catalytic Activity for the Oxidative Dehydrogenation of Secondary Amines.
Authors: Khatri Praveen K. , Jain Suman L. , Sivakumar K. L. N. , Sain Bir
Published: August 2011

A Co(II) Schiff base is successfully immobilized on polyethylene glycol methyl ether MeO‐PEG5000 by use of a triazole linker.
ChemInform Abstract: Highly Efficient Pd/SiO2—Dimethyl Sulfoxide Catalyst System for Selective Semihydrogenation of Alkynes.
Authors: Takahashi Yusuke , Hashimoto Norifumi , Hara Takayoshi , Shimazu Shogo , Mitsudome Takato , Mizugaki Tomoo , Jitsukawa Koichiro , Kaneda Kiyotomi
Published: August 2011

A new method for the selective hydrogenation of alkynes is presented employing a catalytic system consisting of silica‐supported Pd nanoparticles in combination with a minor amount of DMSO.
ChemInform Abstract: Copper‐Catalyzed α‐Amination of Aliphatic Aldehydes.
Authors: Tian Jie‐Sheng , Loh Teck‐Peng
Published: August 2011

Secondary amines with benzylic or allylic protecting groups [cf.
ChemInform Abstract: Copper‐Catalyzed γ‐Selective and Stereospecific Allylic Alkylation of Ketene Silyl Acetals.
Authors: Li Dong , Ohmiya Hirohisa , Sawamura Masaya
Published: August 2011

Under optimized conditions concerning the diketone ligand, allylic phosphates and silyl acetals undergo the title reaction with excellent γ‐ and (E)‐selectivity and excellent functional group compatibility.
ChemInform Abstract: First Bovine Serum Albumin‐Promoted Synthesis of Enones, Cinnamic Acids and Coumarins in Ionic Liquid: An Insight into the Role of Protein Impurities in Porcine Pancreas Lipase for Olefinic Bond Formation.
Authors: Sharma Nandini , Sharma Upendra K. , Kumar Rajesh , Katoch Nidhi , Kumar Rakesh , Sinha Arun K.
Published: August 2011

Aldol condensation of aldehydes with acetone, Knoevenagel reaction with various active methylene compounds and Knoevenagel—Doebner condensation with malonic acid, are effectively catalyzed by bovine serum albumin in the presence of [bmim]Br.
ChemInform Abstract: Rate Enhanced Olefin Cross‐Metathesis Reactions: The Copper Iodide Effect.
Authors: Voigtritter Karl , Ghorai Subir , Lipshutz Bruce H.
Published: August 2011

CuI is found to be an efficient cocatalyst for olefin cross‐metathesis reactions.
ChemInform Abstract: Palladium‐Catalyzed Alkoxy‐ and Aminocarbonylation of Vinyl Tosylates.
Authors: Reeves Diana C. , Rodriguez Sonia , Lee Heewon , Haddad Nizar , Krishnamurthy Dhileepkumar , Senanayake Chris H.
Published: August 2011

A variety of primary, secondary and tertiary alcohols and primary or secondary amines is applied.
ChemInform Abstract: Bis[(L)prolinato‐N,O]Zn in Acetic Acid‐Water: A Novel Catalytic System for the Synthesis of β‐Amino Carbonyls via Mannich Reaction at Room Temperature.
Authors: Kidwai Mazaahir , Jain Arti , Poddar Roona , Bhardwaj Saurav
Published: August 2011

Water as a green solvent, low loadings of a cheep and easily prepared catalyst, high yields, and easy product isolation by simple filtration are the advantages of the title procedure.
ChemInform Abstract: Asymmetric Vinylogous Mukaiyama Aldol Reaction of Aldehyde‐Derived Dienolates.
Authors: Gieseler Marc T. , Kalesse Markus
Published: August 2011

The reaction is promoted by oxazaborolidinones (I) with derivative (Ia) providing the products with mostly higher enantioselectivity.
ChemInform Abstract: Unprecedented Substoichiometric Use of Hazardous Aryl Diazonium Salts in the Heck—Matsuda Reaction via a Double Catalytic Cycle.
Authors: Le Callonnec Francois , Fouquet Eric , Felpin Francois‐Xavier
Published: August 2011

A new, simple, safe, and environmentally friendly method to prepare 2‐arylated acrylates is reported via in situ generation of aryl diazonium salts.
ChemInform Abstract: Regio‐ and Stereoselective Synthesis of 2‐Amino‐1,3‐diene Derivatives by Ruthenium‐Catalyzed Coupling of Ynamides and Ethylene.
Authors: Saito Nozomi , Saito Keiichi , Shiro Motoo , Sato Yoshihiro
Published: August 2011

A new, regio‐ and stereoselective approach to a number of 2‐amino‐1,3‐dienes is given.
ChemInform Abstract: Copper‐Catalyzed Synthesis of 2,4‐Disubstituted Allenoates from α‐Diazoesters.
Authors: Hassink Matthew , Liu Xiaozhong , Fox Joseph M.
Published: August 2011

The reaction requires the use of K2CO3 and 2 equiv.
ChemInform Abstract: N2,N2′‐Disubstituted Oxalic Acid Bishydrazides: Novel Ligands for Copper‐Catalyzed C—N Coupling Reactions in Water.
Authors: Meng Fei , Wang Chenxia , Xie Jianwei , Zhu Xinhai , Wan Yiqian
Published: August 2011

A novel, practical, and economic catalytic system is developed for the N‐arylation of aromatic and aliphatic amines with aryl bromides and iodides in water.
ChemInform Abstract: Nucleophilic Deoxyfluorination of Catechols.
Authors: Nemoto Hiroyuki , Nishiyama Tsuyoshi , Akai Shuji
Published: August 2011

The first method for the nucleophilic deoxyfluorination of one of the two hydroxyl groups of catechols and related compounds is reported.
ChemInform Abstract: Rhodium(NHC)‐Catalyzed O‐Arylation of Aryl Bromides.
Authors: Kim Hyun Jin , Kim Min , Chang Sukbok
Published: August 2011

Two different protocols are developed to overcome a poor functional group tolerance in the etherification reaction of phenols with aryl halides.
ChemInform Abstract: Utilization of Natural Sunlight and Air in the Aerobic Oxidation of Benzyl Halides.
Authors: Su Yijin , Zhang Liangren , Jiao Ning
Published: August 2011

Both bromides and chlorides as leaving groups are equally well tolerated.
ChemInform Abstract: Palladium‐Catalyzed Mono‐α‐arylation of Acetone with Aryl Halides and Tosylates.
Authors: Hesp Kevin D. , Lundgren Rylan J. , Stradiotto Mark
Published: August 2011

Acetone is selectively arylated at one α‐position by aryl chlorides, bromides, iodides, or tosylates using an appropriately designed P,N‐ligand.
ChemInform Abstract: Irreversible Catalytic Ester Hydrolysis of Allyl Esters to Give Acids and Aldehydes by Homogeneous Ruthenium and Ruthenium/Palladium Dual Catalyst Systems.
Authors: Nakamura Asami , Hamasaki Akiyuki , Goto Sachihiko , Utsunomiya Masaru , Tokunaga Makoto
Published: August 2011

The reaction proceeds via isomerization of the allyl esters to 1‐propenyl esters.
ChemInform Abstract: Synthesis of α‐Aryl Nitriles Through Palladium‐Catalyzed Decarboxylative Coupling of Cyanoacetate Salts with Aryl Halides and Triflates.
Authors: Shang Rui , Ji Dong‐Sheng , Chu Ling , Fu Yao , Liu Lei
Published: August 2011

Monoarylated nitriles are selectively prepared.
ChemInform Abstract: Copper Oxide Nanoparticles Catalyzed Synthesis of Aryl Sulfides via Cascade Reaction of Aryl Halides with Thiourea.
Authors: Reddy K. Harsha Vardhan , Reddy V. Prakash , Shankar J. , Madhav B. , Kumar B. S. P. Anil , Nageswar Y. V. D.
Published: August 2011

A broad spectrum of symmetrical disulfides is available under mild conditions in the absence of any additive or foul‐smelling thiol.(Het)aryl iodides are the substrates of choice for the process; with bromides, the reaction is prolonged and the yields are decreased.
ChemInform Abstract: A Facile Synthesis of Unsymmetrical Ureas.
Authors: Bogolubsky Andrey V. , Ryabukhin Sergey V. , Pipko Sergey E. , Lukin Oleg , Shivanyuk Alexander , Mykytenko Dmytro , Tolmachev Andrey
Published: August 2011

Chlorocarbonate (III), prepared by a new method, is transformed in 2 steps to the ureas.
ChemInform Abstract: Recyclable Catalysts for Suzuki—Miyaura Cross‐Coupling Reactions at Ambient Temperature Based on a Simple Merrifield Resin Supported Phenanthroline—Palladium(II) Complex.
Authors: Yang Jin , Li Pinhua , Wang Lei
Published: August 2011

The process can be applied to a broad spectrum of boronic acids and especially, aryl bromides.
ChemInform Abstract: Novel Synthesis of Pinacols and Sulfones Promoted by Sm—NiCl2 Bimetallic System.
Authors: Ye Yuyuan , Zhou Qizhong , Zheng Renhua , Jiang Huajiang , Chen Rener , Zhang Yongmin
Published: August 2011

The main advantages are the mild reaction conditions and the simple operation.
ChemInform Abstract: Carbonylative Heck Reactions Using CO Generated ex situ in a Two‐Chamber System.
Authors: Hermange Philippe , Goegsig Thomas M. , Lindhardt Anders T. , Taaning Rolf H. , Skrydstrup Troels
Published: August 2011

The reaction of various aryl iodides and styrene derivatives with carbon monoxide, generated from fluorene derivative (I), leads to the desired ketones with moderate yields.
ChemInform Abstract: Silver Hexafluoroantimonate Catalyzed Three‐Component [2 + 2 + 1] Cycloadditions of Allenoates, Dual Activated Olefins, and Isocyanides.
Authors: Li Jian , Liu Yuejin , Li Chunju , Jia Xueshun
Published: August 2011

Functionalized cyclopentanones are generally generated from allenoates, isonitriles and arylidenemalonitriles.