bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological study on the reactivity of styrene‐divinylbenzene copolymers in a chloromethylation reaction
Authors: Teixeira Viviane G. , Coutinho Fernanda M. B.
Published: June 2010

Styrene‐divinylbenzene (S‐DVB) copolymers with different kinds of porous structures were synthesized by aqueous suspension polymerization using n‐heptane as the pore forming agent. The amount of this solvent (monomer dilution degree) and the DVB content in the organic phase were varied. The combination of three different dilution degree values and three DVB contents yielded three series of copolymers with a variety of porous structures. The three series were composed by copolymers with pore diameters (D) in the following ranges: D < 500 Å, 500 < D < 1000 Å, and D > 1000 Å, respectively. The effect of synthesis conditions on the pore size distribution and on the copolymer matrix rigidity was evaluated. These copolymers were submitted to a chloromethylation reaction with a paraformaldehyde/gaseous HCl mixture in the presence of zinc chloride as a Lewis acid catalyst and 1,2‐dichloroethane as solvent. The effect of the copolymer porosity on the chloromethylation reaction extension was evaluated. It was possible to observe that a gel copolymer with a high swelling capacity in the reaction medium achieved the same chloromethylation yield observed for a high porous copolymer. This result thus indicates that, in the case of the chloromethylation reaction studied here, the high swelling capacity of the gel copolymer can counterbalance its limited surface area, turning this type of polymer structure as reactive as a macroporous one. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Development of colorimetric analytical methods to monitor quaternary amine grafted surfaces
Authors: Ozer Ruya R. , Hill W. Cary , Rogers Martin E. , Evans Mishell
Published: June 2010

Quick and simple colorimetric analytical techniques were developed to monitor functionalization of surfaces with quaternary amine bearing polymers as complementary qualitative tests to the traditionally used antimicrobial test protocols. First, an established antimicrobial quaternary ammonium salt (QAS) was chosen as a probe compound and an acrylol functional group was introduced (acrylol‐QAS) to facilitate its polymerization with acrylic monomers. Surface graft polymerization was carried out with methyl methacrylate (MMA) and acrylol‐QAS on cotton fabric surface. The success of graft polymerization, durability after repetitive aqueous extraction, and the effect of crosslinking agents on the durability and extent of polymerization were tested with a fluorescein spot and a bromophenol solution test. The results of these colorimetric analytical methods were in perfect agreement with those of antimicrobial tests, XPS, and SEM analysis. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Properties of poly(ethylene glycol)‐based bioelastomers
Authors: Tao Ding , Yuanqing Xu , Huang Gu , Yurong Liang , Xiaomin Fang , Liqun Zhang
Published: June 2010

In this article, a series of poly(ether ester) bioelastomers, poly(PEG‐co‐CA)s (PECs), were synthesized by the melt polycondensation of citric acid (CA) and poly(ethylene glycol) (PEG) with molecular weights of 150, 200, 300, and 400. The measurements of the mechanical properties of the PEC series testified that these polymers were elastomers with a low hardness and high elongation, and the hydrolytic degradation of polymer films in a buffer of pH 7.4 at 37°C showed that the PECs had excellent degradability. The molecular weight of PEG had a strong influence on the degradation rates, water absorption rates, and mechanical performance of the PECs. The materials are expected to be useful for pressure hemostasis implementation in lacuna and other biomedical applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and properties of poly(urethane acrylate) films for ultraviolet‐curable coatings
Authors: Seo Jongchul , Jang Eui‐Sung , Song Jin‐Han , Choi Seunghyuk , Khan Sher Bahadar , Han Haksoo
Published: June 2010

Four different UV‐curable poly(urethane acrylate)s were prepared through the reaction of two diisocyanates [i.e., toluene‐2,4‐diisocyanate (TDI) and isophorone diisocyanate (IPDI)] and two polyols [i.e., polycaprolactone triol (PCLT) and polycaprolactone diol (PCLD)], and they were characterized with Fourier transform infrared spectroscopy. The mechanical properties, thermal properties, and water sorption of the cured poly(urethane acrylate)s were also investigated with respect to the chemical structures of the polyols and diisocyanates. In comparison with linear PCLD–TDI and PCLD–IPDI, crosslinked PCLT–TDI and PCLT–IPDI with trifunctional PCLT showed relatively high thermal decomposition temperatures. The hardness and modulus of the UV‐cured poly(urethane acrylate) films, which were measured by a nanoindentation technique, were in the following increasing order: PCLD–IPDI ∼ PCLD–TDI < PCLT–IPDI ∼ PCLT–TDI. The pencil hardness was 3H for PCLT–IPDI and PCLT–TDI and HB for PCLD–IPDI and PCLD–TDI. Two urethane acrylates prepared from the trifunctional polyol showed better acid and alkali resistances than those made from the bifunctional polyol. These mechanical properties and chemical resistances may have been strongly dependent on the chain flexibility of the molecules and crosslinking density. Regardless of the functionality in the polyol, the change in the yellowness index showed a lower value in the poly(urethane acrylate) coating containing the aliphatic diisocyanate IPDI in comparison with the corresponding poly(urethane acrylate) with the aromatic diisocyanate TDI. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of the organoclay preparation on the extent of intercalation/exfoliation and barrier properties of polyethylene/PA6/montmorillonite nanocomposites
Authors: Erdmann Eleonora , Acosta Delicia , Pita Victor J. R. R. , Monasterio Fernanda E. , Carrera María C. , Dias Marcos L. , Destéfanis Hugo A.
Published: June 2010

Nanocomposites of HDPE matrix and 3 wt % organoclay/PA6 discontinuous phase were prepared in a mixer chamber. These nanocomposites of organoclay, PA6, and HDPE were characterized by X‐ray diffraction, scanning electron and transmission electron microscopy (SEM and TEM). Barrier properties were determined by cyclohexane pervaporation and solubility. The results show that the degree of exfoliation and/or intercalation and the barrier properties depend on a combination of the proper chemical treatment and optimized processing in these polyethylene‐organoclays nanocomposites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A new adaptive PI for bicarbonate regulation in an anaerobic digestion process
Authors: Carlos‐Hernandez Salvador
Published: June 2010

This paper deals with the design and validation via numerical simulations of an adaptive proportional integral (PI) controller for bicarbonate regulation in an anaerobic wastewater treatment process. The proportional and integral gains are deduced as a function of the parameters of an approximate dynamical model. First, a brief explanation of the control structure is introduced. After that, a general equation of an adaptive PI controller is proposed. Next, the controller is implemented in order to regulate bicarbonate by two control actions in a completely stirred tank reactor (CSTR): adding a base and manipulating the dilution rate. Finally, a smooth switching mechanism which allows the process to operate in open or closed loop according to the operating conditions is implemented. The performance of the process with the proposed control scheme is validated via simulations. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Conformational dynamics of active site loop in Escherichia coli phytase
Authors: Shivange Amol V. , Schwaneberg Ulrich , Roccatano Danilo
Published: June 2010

Phytases catalyze the release of phosphate by stepwise hydrolysis of phytate, a major source of phosphate in cereal grains, legumes, and oilseeds. Phytase improves, as a feed supplement, the nutritional quality of phytate rich diets and eventually reduce environmental pollution. Recently, phytases from enterobacteriaceae family have attracted industrial interest due to their high specific activity (2500–4000 U/mg). However, only limited information is available concerning structural dynamics of this class of enzymes. In this study, 50 nanosecond molecular dynamics simulation was performed on two Escherichia coli phytase structures (closed and open active site loop) to investigate conformational dynamics of the active site loop. Cluster analysis and principal component analysis (PCA) reveal significant difference in the conformational dynamics of active site compared to reported crystal structure. Molecular dynamic studies indicated that the movement in the active site of E. coli phytase is mainly confined by the active site loop resulted in wider opening of the loop in absence of phytate. The molecular dynamics studies highlight the possible role of loop residues as prerequisite for highly active phytases. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 994–1002, 2010.
Gase als zelluläre Signalstoffe. Gasotransmitter
Authors: Hermann Anton , Sitdikova Guzel F. , Weiger Thomas M.
Published: June 2010

Die Gase Stickoxid (NO), Kohlenmonoxid (CO) und Schwefelwasserstoff (H2S) werden aufgrund ihrer Wirkung als Signalstoffe als “Gasotransmitter” zusammengefasst. Diese Gase spielen eine wichtige Rolle als intra‐ und interzellulärer Signalstoff im Verdauungs‐, Atmungs‐ oder Urogenitalsystem, bei der Steuerung des Herzschlags oder Nervenaktivitäten. Die Forschung ist dabei, Funktionen und weitere Details der Wirkmechanismen dieser Gase und ihre Implikationen für Physiologie, Pathophysiologie und Pharmakologie zu erarbeiten. Vom bisher neuesten Kandidaten – dem H2S – gibt es Hinweise, dass er in hoher Konzentration im Gehirn und in den Hoden vorkommt und bei Lern‐/Gedächtnisprozessen sowie bei Geschlechtsfunktionen eine Rolle spielt. Durch Entwicklung von Wirksubstanzen zur Beeinflussung der H2S‐Produktion oder entsprechender Zielorte könnte sich hieraus ein interessantes pharmakologisches Potenzial entwickeln.
Neues Leben im Weltnaturerbe Wattenmeer. Globalisierung unter Wasser
Authors: Buschbaum Christian , Reise Karsten
Published: June 2010

Neue Untersuchungen im Wattenmeer decken eine Überflutung durch eingeschleppte Arten auf, die sich in den vergangenen Jahren vor allem im Flachwasserbereich direkt unterhalb der Gezeitenzone ausbreiten konnten. Hier sind sie Nutznießer der durch den globalen Klimawandel verursachten ansteigenden Wassertemperaturen. Entstanden ist eine diverse Lebensgemeinschaft von Algen und Wirbellosen, die sich fortlaufend weiter verändert. Neben der strukturellen Komplexität der biogenen Habitate hat besonders die funktionelle Gruppe der filtrierenden Organismen zugenommen. Insgesamt ist das gesamte Ökosystem in einen Umbruch geraten, der nicht mehr umkehrbar ist.
Evolutionärer Stammbaum der Blütenpflanzen – neue Zugehörigkeiten, neue Namen
Authors: Cole Theodor C. H.
Published: June 2010

Seit Jahrhunderten bemühen sich Botaniker, “Ordnung ins System” zu bringen – für die Blütenpflanzen ist man diesem Ziel nun sehr nah. Ein Konsortium international führender Pflanzensystematiker hat die Ergebnisse der molekularen Phylogenie der vergangenen drei Jahrzehnte zusammengefasst und unter Berücksichtigung morphologisch‐anatomischer und chemotaxonomischer Gesichtpunkte daraus die Verwandtschaftsbeziehungen der Blütenpflanzen reinterpretiert. Es resultiert ein evolutionär begründeter Stammbaum, der auf der Ebene der Hauptgruppen (Ordnungen und Familien) nun ein hohes Maß an Stabilität aufweist.
Nachrichten des Verbandes Biologie, Biowissenschaften & Biomedizin in Deutschland
Authors: Tautz Diethard
Published: June 2010

Aus den Fachgesellschaften:

Deutsche Ornithologen‐Gesellschaft

Bundesdelegiertenversammlung

Ausbildung und Karriere

Landesverbände:

Nordrhein‐Westfalen

Baden‐Württemberg

Saarland

Rheinland‐Pfalz
Syngas fermentation to biofuel: Evaluation of carbon monoxide mass transfer coefficient (kLa) in different reactor configurations
Authors: Munasinghe Pradeep Chaminda , Khanal Samir Kumar
Published: June 2010

Lignocellulosic biomass such as agri‐residues, agri‐processing by‐products, and energy crops do not compete with food and feed, and is considered to be the ideal renewable feedstocks for biofuel production. Gasification of biomass produces synthesis gas (syngas), a mixture primarily consisting of CO and H2. The produced syngas can be converted to ethanol by anaerobic microbial catalysts especially acetogenic bacteria such as various clostridia species.One of the major drawbacks associated with syngas fermentation is the mass transfer limitation of these sparingly soluble gases in the aqueous phase. One way of addressing this issue is the improvement in reactor design to achieve a higher volumetric mass transfer coefficient (kLa). In this study, different reactor configurations such as a column diffuser, a 20‐μm bulb diffuser, gas sparger, gas sparger with mechanical mixing, air‐lift reactor combined with a 20‐μm bulb diffuser, air‐lift reactor combined with a single gas entry point, and a submerged composite hollow fiber membrane (CHFM) module were employed to examine the kLa values. The kLa values reported in this study ranged from 0.4 to 91.08 h−1. The highest kLa of 91.08 h−1 was obtained in the air‐lift reactor combined with a 20‐μm bulb diffuser, whereas the reactor with the CHFM showed the lowest kLa of 0.4 h−1. By considering both the kLa value and the statistical significance of each configuration, the air‐lift reactor combined with a 20‐μm bulb diffuser was found to be the ideal reactor configuration for carbon monoxide mass transfer in an aqueous phase. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2011
Streptococcus mutans Inhibits Candida albicans Hyphal Formation by the Fatty Acid Signaling Molecule trans‐2‐Decenoic Acid (SDSF)
Authors: Vílchez Ramiro , Lemme André , Ballhausen Britta , Thiel Verena , Schulz Stefan , Jansen Rolf , Sztajer Helena , Wagner‐Döbler Irene
Published: June 2010

In the human mouth, fungi and several hundred species of bacteria coexist. Here we report a case of interkingdom signaling in the oral cavity: A compound excreted by the caries bacterium Streptococcus mutans inhibits the morphological transition from yeast to hyphae, an important virulence trait, in the opportunistic fungus Candida albicans. The compound excreted by S. mutans was originally studied because it inhibited signaling by the universal bacterial signal autoinducer‐2 (AI‐2), determined by the luminescence of a Vibrio harveyi sensor strain. The inhibitor was purified from cell‐free culture supernatants of S. mutans guided by its activity. Its chemical structure was elucidated by using NMR spectroscopy and GC‐MS and proved to be trans‐2‐decenoic acid. We show that trans‐2‐decenoic acid does not inhibit AI‐2‐specific signaling, but rather the luciferase reaction used for its detection. A potential biological role of trans‐2‐decenoic acid was then discovered. It is able to suppress the transition from yeast to hyphal morphology in the opportunistic human pathogen Candida albicans at concentrations that do not affect growth. The expression of HWP1, a hyphal‐specific signature gene of C. albicans, is abolished by trans‐2‐decenoic acid. trans‐2‐Decenoic acid is structurally similar to the diffusible signal factor (DSF) family of interkingdom‐signaling molecules and is the first member of this family from a Gram‐positive organism (Streptococcus DSF, SDSF). SDSF activity was also found in S. mitis, S. oralis, and S. sanguinis, but not in other oral bacteria. SDSF could be relevant in shaping multispecies Candida bacteria biofilms in the human body.
An RNA Aptamer That Selectively Inhibits the Enzymatic Activity of Protein Tyrosine Phosphatase 1B in vitro
Authors: Townshend Brent , Aubry Isabelle , Marcellus Richard C. , Gehring Kalle , Tremblay Michel L.
Published: June 2010

SELEX was used to create an RNA aptamer targeted to protein tyrosine phosphatase 1B (PTP1B), an enzyme implicated in type 2 diabetes, breast cancer and obesity. We found an aptamer that strongly inhibits PTP1B in vitro with a Ki of less than 600 pM. This slow‐binding, high‐affinity inhibitor is also highly selective, with no detectable effect on most other tested phosphatases and approximately 300:1 selectivity over the closely related TC‐PTP. Through controlled synthesis of truncated variants of the aptamer, we isolated shorter forms that inhibit PTP1B. We also investigated various single‐nucleotide modifications to probe their effects on the aptamer's secondary structure and inhibition properties. This family of aptamers represents an exciting option for the development of lead nucleotide‐based compounds in combating several human cancers and metabolic diseases.
The Torsional Barriers of 2‐Hydroxy‐ and 2‐Fluorobiphenyl: Small but Measurable
Authors: Mazzanti Andrea , Lunazzi Lodovico , Ruzziconi Renzo , Spizzichino Sara , Schlosser Manfred
Published: June 2010

By making use of a novel diastereotopicity probe, namely C(CF3)2OH, it has been possible to measure by very low temperature 19F NMR spectroscopy the elusive aryl–aryl rotation barriers of biphenyls bearing an OH or F group in one ortho position. The experimental values (5.4 and 4.4 kcal mol−1, respectively) are matched by those from ab initio calculations (5.3 and 4.3 kcal mol−1, respectively).
The Wacker Process: Inner‐ or Outer‐Sphere Nucleophilic Addition? New Insights from Ab Initio Molecular Dynamics
Authors: Comas‐Vives Aleix , Stirling András , Lledós Agustí , Ujaque Gregori
Published: June 2010

The Wacker process consists of the oxidation of ethylene catalyzed by a PdII complex. The reaction mechanism has been largely debated in the literature; two modes for the nucleophilic addition of water to a Pd‐coordinated alkene have been proposed: syn‐inner‐ and anti‐outer‐sphere mechanisms. These reaction steps have been theoretically evaluated by means of ab initio molecular dynamics combined with metadynamics by placing the [Pd(C2H4)Cl2(H2O)] complex in a box of water molecules, thereby resembling experimental conditions at low [Cl−]. The nucleophilic addition has also been evaluated for the [Pd(C2H4)Cl3]− complex, thus revealing that the water by chloride ligand substitution trans to ethene is kinetically favored over the generally assumed cis species in water. Hence, the resulting trans species can only directly undertake the outer‐sphere nucleophilic addition, whereas the inner‐sphere mechanism is hindered since the attacking water is located trans to ethene. In addition, all the simulations from the [Pd(C2H4)Cl2(H2O)] species (either cis or trans) support an outer‐sphere mechanism with a free‐energy barrier compatible with that obtained experimentally, whereas that for the inner‐sphere mechanism is significantly higher. Moreover, additional processes for a global understanding of the Wacker process in solution have also been identified, such as ligand substitutions, proton transfers that involve the aquo ligand, and the importance of the trans effect of the ethylene in the nucleophilic addition attack.
Theoretical Design of High‐Spin Polycyclic Hydrocarbons
Authors: Trinquier Georges , Suaud Nicolas , Malrieu Jean‐Paul
Published: June 2010

High‐spin organic structures can be obtained from fused polycyclic hydrocarbons, by converting selected peripheral HC(sp2) sites into H2C(sp3) ones, guided by Ovchinnikov’s rule. Theoretical investigation is performed on a few examples of such systems, involving three to twelve fused rings, and maintaining threefold symmetry. Unrestricted DFT (UDFT) calculations, including geometry optimizations, confirm the high‐spin multiplicity of the ground state. Spin‐density distributions and low‐energy spectra are further studied through geometry‐dependent Heisenberg–Hamiltonian diagonalizations and explicit correlated ab initio treatments, which all agree on the high‐spin character of the suggested structures, and locate the low‐lying states at significantly higher energies. In particular, the lowest‐lying state of lower multiplicity is always found to be higher than kT at room temperature (at least ten times higher). Simplification of the ferromagnetic organization based on sets of semilocalized nonbonding orbitals is proposed. Molecular architectures are thus conceived in which the ferromagnetically‐coupled unpaired electrons tally up to one third of the involved conjugated carbons. Connecting such building blocks should provide bidimensional materials endowed with robust magnetic properties.
Sonication‐Triggered Instantaneous Gel‐to‐Gel Transformation
Authors: Yu Xudong , Liu Qian , Wu Junchen , Zhang Mingming , Cao Xinhua , Zhang Song , Wang Qi , Chen Liming , Yi Tao
Published: June 2010

Two new peptide‐based isomers containing cholesterol and naphthalic groups have been designed and synthesized. We found that the position of L‐alanine in the linker could tune the gelation properties and morphologies. The molecule with the L‐alanine residue positioned in the middle of the linker (1 b) shows better gelation behavior than that with L‐alanine directly linked to the naphthalimido moiety (1 a). As a result, a highly thermostable organogel of 1 b with a unique core–shell structure was obtained at high temperature and pressure in acetonitrile. Moreover, the gels of 1 a and 1 b could undergo an instantaneous gel‐to‐gel transition triggered by sonication. Ultrasound could break the core–shell microsphere of 1 b and the micelle structure of 1 a into entangled fibers. By studying the mechanism of the sonication‐triggered gel‐to‐gel transition process of these compounds, it can be concluded that ultrasound has a variety of effects on the morphology, such as cutting, knitting, unfolding, homogenizing, and even cross‐linking. Typically, ultrasound can cleave and homogenize π‐stacking and hydrophobic interactions among the gel molecules and then reshape the morphologies to form a new gel. This mechanism of morphology transformation triggered by sonication might be attractive in the field of material storage and controlled release.
Cationic Reverse Micelles Create Water with Super Hydrogen‐Bond‐Donor Capacity for Enzymatic Catalysis: Hydrolysis of 2‐Naphthyl Acetate by α‐Chymotrypsin
Authors: Moyano Fernando , Falcone R. Dario , Mejuto J. C. , Silber Juana J. , Correa N. Mariano
Published: June 2010

Reverse micelles (RMs) are very good nanoreactors because they can create a unique microenvironment for carrying out a variety of chemical and biochemical reactions. The aim of the present work is to determine the influence of different RM interfaces on the hydrolysis of 2‐naphthyl acetate (2‐NA) by α‐chymotrypsin (α‐CT). The reaction was studied in water/benzyl‐n‐hexadecyldimethylammonium chloride (BHDC)/benzene RMs and, its efficiency compared with that observed in pure water and in sodium 1,4‐bis‐2‐ethylhexylsulfosuccinate (AOT) RMs. Thus, the hydrolysis rates of 2‐NA catalyzed by α‐CT were determined by spectroscopic measurements. In addition, the method used allows the joint evaluation of the substrate partition constant Kp between the organic and the micellar pseudophase and the kinetic parameters: catalytic rate constant kcat, and the Michaelis constant KM of the enzymatic reaction. The effect of the surfactant concentration on the kinetics parameters was determined at constant W0=[H2O]/[surfactant], and the variation of W0 with surfactant constant concentration was investigated. The results show that the classical Michaelis–Menten mechanism is valid for α‐CT in all of the RMs systems studied and that the reaction takes place at both RM interfaces. Moreover, the catalytic efficiency values kcat/KM obtained in the RMs systems are higher than that reported in water. Furthermore, there is a remarkable increase in α‐CT efficiency in the cationic RMs in comparison with the anionic system, presumably due to the unique water properties found in these confined media. The results show that in cationic RMs the hydrogen‐bond donor capacity of water is enhanced due to its interaction with the cationic interface. Hence, entrapped water can be converted into “super‐water” for the enzymatic reaction studied in this work.
Preparation of Organoaluminum Reagents from Propargylic Bromides and Aluminum Activated by PbCl2 and Their Regio‐ and Diastereoselective Addition to Carbonyl Derivatives
Authors: Guo Li‐Na , Gao Hongjun , Mayer Peter , Knochel Paul
Published: June 2010

Various propargylic and allenic aluminum reagents have been easily prepared by a direct insertion of aluminum into propargylic bromides in the presence of PbCl2 (1 mol %). These organoaluminum reagents react with carbonyl compounds to afford the corresponding allenic alcohols or homopropargylic alcohols in good to excellent yields with high regio‐ and diastereoselectivity.
Reactivity of the Latent 12‐Electron Fragment [Rh(PiBu3)2]+ with Aryl Bromides: ArylBr and Phosphine Ligand CH Activation
Authors: Townsend Nell S. , Chaplin Adrian B. , Naser M. Abu , Thompson Amber L. , Rees Nicholas H. , Macgregor Stuart A. , Weller Andrew S.
Published: June 2010

Oxidative addition of aryl bromides to 12‐electron [Rh(PiBu3)2][BArF4] (ArF=3,5‐(CF3)2C6H3) forms a variety of products. With p‐tolyl bromides, RhIII dimeric complexes result [Rh(PiBu3)2(o/p‐MeC6H4)(μ‐Br)]2[BArF4]2. Similarly, reaction with p‐ClC6H4Br gives [Rh(PiBu3)2(p‐ClC6H4)(μ‐Br)]2[BArF4]2. In contrast, the use of o‐BrC6H4Me leads to a product in which toluene has been eliminated and an isobutyl phosphine has undergone CH activation: [Rh{PiBu2(CH2CHCH3CH2)}(PiBu3)(μ‐Br)]2[BArF4]2. Trapping experiments with ortho‐bromo anisole or ortho‐bromo thioanisole indicate that a possible intermediate for this process is a low‐coordinate RhIII complex that then undergoes CH activation. The anisole and thioanisole complexes have been isolated and their structures show OMe or SMe interactions with the metal centre alongside supporting agostic interactions, [Rh(PiBu3)2(C6H4OMe)Br][BArF4] (the solid‐state structure of the 5‐methyl substituted analogue is reported) and [Rh(PiBu3)2(C6H4SMe)Br][BArF4]. The anisole‐derived complex proceeds to give [Rh{PiBu2(CH2CHCH3CH2)}(PiBu3)(μ‐Br)]2[BArF4]2, whereas the thioanisole complex is unreactive. The isolation of [Rh(PiBu3)2(C6H4OMe)Br][BArF4] and its onward reactivity to give the products of CH activation and aryl elimination suggest that it is implicated on the pathway of a σ‐bond metathesis reaction, a hypothesis strengthened by DFT calculations. Calculations also suggest that CH bond cleavage through phosphine‐assisted deprotonation of a non‐agostic bond is also competitive, although the subsequent protonation of the aryl ligand is too high in energy to account for product formation. CH activation through oxidative addition is also ruled out on the basis of these calculations. These new complexes have been characterised by solution NMR/ESIMS techniques and in the solid‐state by X‐ray crystallography.
Preparation of Imidazolin‐2‐iminato Molybdenum and Tungsten Benzylidyne Complexes: A New Pathway to Highly Active Alkyne Metathesis Catalysts
Authors: Haberlag Birte , Wu Xian , Brandhorst Kai , Grunenberg Jörg , Daniliuc Constantin G. , Jones Peter G. , Tamm Matthias
Published: June 2010

The reaction of [PhCMBr3(dme)] (dme=1,2‐dimethoxyethane) with the hexafluoro‐tert‐butoxides LiX or KX [X=OC(CF3)2Me] afforded the benzylidyne complexes [PhCMX3(dme)] (2 a: M=W, 2 b: M=Mo), which further reacted with the lithium reagent Li(ImtBuN), generated with MeLi from 1,3‐di‐tert‐butylimidazolin‐2‐imine (ImtBuNH), to form the imidazolin‐2‐iminato complexes [PhCMX2(ImtBuN)] (3 a: M=W, 3 b: M=Mo). The propylidyne complex [EtCMoX2(NImtBu)] (4) was obtained by treatment of 3 b with an excess of 3‐hexyne. Complexes 3 a and 3 b are able to efficiently catalyse alkyne cross metathesis of various 3‐pentynyl benzyl ethers 5 and benzoic esters 7 at room temperature, to afford 2‐butyne and the corresponding diethers 6 and diesters 8. The tungsten complex 3 a proved to be a superior catalyst for ring‐closing alkyne metathesis, and the [10]cyclophanes 10 and 12 were synthesised in high yield from 1,3‐bis(3‐pentynyloxymethyl)benzene (9) and bis(3‐pentynyl) phthalate (11), respectively. The molecular structures of compounds 2 a, 2 b, 3 a, 3 b, 4, and 12 were determined by single‐crystal X‐ray diffraction. DFT calculations have been carried out for catalyst systems based on the imidazolin‐2‐iminato tungsten and molybdenum complexes 3 a and 3 b by choosing the alkyne metathesis of 2‐butyne as the model reaction; the studies revealed a lower activation barrier for the tungsten system.
Ferrocene‐Substituted Dithio‐o‐Carborane Isomers: Influence on the Native Conformation of Myoglobin Protein
Authors: Wu Chunhui , Xu Baohua , Zhao Juan , Jiang Qibai , Wei Fadong , Jiang Hui , Wang Xuemei , Yan Hong
Published: June 2010

Biointeractions between two organometallic compounds, a pair of ferrocene‐substituted dithio‐o‐carborane isomers (C14H20B10FeS2; denoted as FcSB1 and FcSB2), and myoglobin (Mb) have been investigated by means of electrochemistry, fluorescence, circular dichroism, and UV/Vis absorption spectroscopy. Our observations demonstrate that FcSB1 and FcSB2 could coordinate to the axial position trans to the histidine imidazole that induces the change of the heme iron from the high spin state to the low spin state and the changes of the conformation of the aromatic fluorophores of the selected heme protein. Such influences attribute to the structural features of FcSB1 and FcSB2 containing sulfur donor atoms and hydrophobic ferrocenyl and carboranyl units that leads to specific binding modalities with Mb. This study provides an insight into the understanding of relevant biointeractions between the new type of ferrocene–carborane conjugates and hemoproteins, and might shed light on the promising bioapplications of these multifunctional organometallic complexes.
ChemInform Abstract: Synthesis and Crystal Structure of Metal(I) Hydrogen Sulfates — Ag(H3O)(HSO4)2, Ag2(HSO4)2(H2SO4), AgHSO4, and Hg2(HSO4)2.
Authors: Stiewe A. , Kemnitz E. , Troyanov S.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Structure of (NH4)2[(AuI4)(MI4)] (M: Ga, In).
Authors: Schulz Lang E. , Abram U. , Straehle J. , Vazquez‐Lopez E. M.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Crystal Structure of Tl2PdCl4.
Authors: Schuepp Barbara , Keller Hans‐Lothar
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: High Rate Electrodes of V2O5 Aerogel.
Authors: Passerini S. , Ressler J. J. , Le D. B. , Owens B. B. , Smyrl W. H.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Anisotropic Templating Effect in the Formation of Two‐Dimensional Anionic Cadmium—Thiocyanate Coordination Solids [(12‐crown‐4)2Cd][Cd2(SCN)6] (I) and [(12‐crown‐4)2Cd][Cd3(SCN)8] (II) with Checkerboard and Herringbone Patterns, Respectively.
Authors: Zhang Hong , Wang Ximin , Zhu H. , Xiao W. , Zhang Kecong , Teo Boon K.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Organothermal Synthesis and Characterization of Nanocrystalline β‐Indium Sulfide.
Authors: Yu Shu‐Hong , Shu Lei , Wu Yong‐Sheng , Yang Jian , Xie Yi , Qian Yi‐Tai
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Gliclazide
Authors: Parvez Masood , Arayne M. Saeed , Zaman M. Kamran , Sultana Najma
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enantioselective Synthesis of β‐Amino Sulfones by Aza‐Michael Addition to Alkenyl Sulfones.
Authors: Enders Dieter , Mueller Stephan F. , Raabe Gerhard
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Transfer Hydrogenation of Ketonic Substrates Catalyzed by (η5‐C5Me5)MCl Complexes (M: Rh and Ir) of (1S,2S)‐N‐(p‐Toluenesulfonyl)‐1,2‐diphenylethylenediamine.
Authors: Mashima Kazushi , Abe Tomoyuki , Tani Kazuhide
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Substrate Specific Chiral Modifier Activation on Enantio‐Differentiating Hydrogenation over Tartaric Acid‐Modified Raney Nickel.
Authors: Nakagawa Satoshi , Sugimura Takashi , Tai Akira
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enantioselective Conjugate Addition of Diethylzinc to Enones Catalyzed by a Copper Complex of Chiral Aryl Diphosphite.
Authors: Yan Ming , Yang Li‐Wei , Wong Kwok‐Yin , Chan Albert S. C.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enantioselective Reduction of Ketones with Triethoxysilane Catalyzed by Chiral Bis‐oxazoline Titanium Complexes.
Authors: Bandini Marco , Cozzi Pier Giorgio , Negro Lucia , Umani‐Ronchi Achille
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of a trans‐Chelating Chiral Diphosphine Ligand with Only Planar Chirality and Its Application to Asymmetric Hydrosilylation of Ketones.
Authors: Kuwano Ryoichi , Uemura Takashi , Saitoh Makoto , Ito Yoshihiko
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Conjugate Addition—Aldol Tandem Reaction of α,β‐Unsaturated Esters Catalyzed by Lithium Benzenethiolate.
Authors: Ono Masashi , Nishimura Katsumi , Nagaoka Yasuo , Tomioka Kiyoshi
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 1,3‐Dipolar Cycloadditions. Part 110. 1,3‐Cycloadditions of Pyridinium N‐Arylimides.
Authors: Huisgen Rolf , Temme Robert
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Molecular Structure of the Aluminum Halides, Al2Cl6, AlCl3, Al2Br6, AlBr3, and AlI3, Obtained by Gas‐Phase Electron Diffraction and ab initio Molecular Orbital Calculations.
Authors: Aarset Kirsten , Shen Quang , Thomassen Hanne , Richardson Alan D. , Hedberg Kenneth
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation, Crystal Structure and IR Spectra of BeSeO3×H2O — Hydrogen Bonds and Correlation of IR and Structure Data in the Monohydrates MSeO3×H2O (M: Be, Ca, Mn, Co, Ni, Zn, Cd).
Authors: Baeumer U. , Boldt K. , Engelen B. , Mueller H. , Unterderweide K.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Thermodynamic Properties of Liquids in the System KF—KBF4.
Authors: Nerad I. , Kosa L. , Adamkovicova K. , Proks I.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: LiSr1.656t0.35M11.3M 21.7O9 (M1: Ti, Zr; M2: Nb, Ta): New Lithium Ion Conductors Based on the Perovskite Structure.
Authors: Thangadurai V. , Shukla A. K. , Gopalakrishnan J.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Laboratory Formation of OBrO and Its Reactivity Toward Ozone at 298 K.
Authors: Li Zhuangjie
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Low‐Temperature Matrix Isolation and Photolysis of BCl2N3: Spectroscopic Identification of the Photolysis Product ClBNCl.
Authors: Johnson Lisa A. , Sturgis Samantha A. , Al‐Jihad Ismail A. , Liu Bing , Gilbert Julanna V.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Contributions to the Chemistry of Phosphorus. Part 241. Reaction of Diphosphane(4) with Liquid Ammonia and with Amines — A New Route to Polyphosphides and Hydrogen Polyphosphides.
Authors: Baudler M. , Winzek P.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: [ScCl2{N(SiMe3)2}(THF)2] — A Precursor for the Synthesis of Scandium Nitride.
Authors: Karl Marc , Seybert Gerd , Massa Werner , Dehnicke Kurt
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Basic Carbonates of Dysprosium: Dy2O2(CO3) and Dy(OH)(CO3).
Authors: Kutlu Ibrahim , Meyer Gerd
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of TiO2 Nanocrystals by Nonhydrolytic Solution‐Based Reactions.
Authors: Trentler Timothy J. , Denler Tiffany E. , Bertone Jane F. , Agrawal Aarti , Colvin Vicki L.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ag2Cu2O3: The First Silver Copper Oxide.
Authors: Gomez‐Romero Pedro , Tejada‐Rosales Eva M. , Palacin M. Rosa
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Stereocontrol in the Intramolecular Buchner Reaction of Diazoamides and Diazoesters.
Authors: Moody Christopher J. , Miah Soyfur , Slawin Alexandra M. Z. , Mansfield Darren J. , Richards Ian C.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Stereocontrol in the Intramolecular Buchner Reaction of Diazoketones.
Authors: Maguire Anita R. , Buckley N. Rachael , O'Leary Patrick , Ferguson George
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Functionalization of a β‐Lactam Ring via Nucleophilic Displacement of a 4‐Vinyloxy Substituent.
Authors: Kaluza Zbigniew
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Lithium Perchlorate‐Accelerated Baylis—Hillmann Reactions.
Authors: Kawamura Mikako , Kobayashi Shu
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Air Oxidative Coupling of Thiols to Disulfides Catalyzed by Fe(III)/NaI.
Authors: Iranpoor N. , Zeynizadeh B.
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Diastereoselective Aldol Reactions of (Z)‐N‐[Bis(methylthio)methylene]‐α,β‐didehydroglutamates.
Authors: Alvarez‐Ibarra Carlos , Csaky Aurelio G. , Murcia M. Carmen
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Microwave‐Assisted Heterogeneous Benzil—Benzilic Acid Rearrangement.
Authors: Yu Hui‐Ming , Chen Same‐Ting , Tseng Min‐Jen , Chen Shui‐Tein , Wang Kung‐Tsung
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Selective 1,4‐Reduction of α,β‐Unsaturated Carbonyl Compounds by Combined Use of Bis(1,3‐diketonato)cobalt(II) Complex and Diisobutylaluminum Hydride.
Authors: Ikeno Taketo , Kimura Tomomi , Ohtsuka Yuhki , Yamada Tohru
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Stereoselective Hydrogenolysis of 1,1‐Dibromo‐1‐alkenes and Stereospecific Synthesis of Conjugated (Z)‐Alkenyl Compounds.
Authors: Uenishi Jun'ichi , Kawahama Reiko , Yonemitsu Osamu , Tsuji Jiro
Published: June 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.