bluuebunny/crossref_metadata_2025_split huggingface dataset:
Highly Stereoselective Synthesis of Arylene‐Silylene‐Vinylene Polymers
Authors: Majchrzak Mariusz , Marciniec Bogdan , Itami Yujiro 
Published: July 2005

AbstractStereoregular trans‐arylene‐silylene‐vinylene polymers of Mw=13100–34800 and PDI=1.6–2.9 of the general formulas CH2CH[SiMe2C6H4‐SiMe2CHCH](16, 17, 18) and CH2CH[(R)CHCHC6H4CHCH](where R=Me2Si‐pC6H4‐ SiMe2, Me2Si‐mC6H4SiMe2 and Me2SiC6H4C6H4SiMe2) (19, 20, 21) have been effectively synthesized via silylative coupling (SC) homopolycondensation of bis(vinyldimethylsilyl)arenes (10, 12, 14) and cross‐polycondensation of 4‐(vinyldimethylsilyl)styrene (11) as well as cross‐copolycondensation of bis(vinyldimethylsilyl)arenes (10, 12 and 14) with 1,4‐divinylbenzene (9) catalyzed by [RuH(Cl)(CO)(PCy3)2] (7). Such highly stereoregular products cannot be synthesized via ADMET polycondensation or ring opening metathesis ROM or polyaddition of hydridosilanes to acetylenes.
Investigation on Aggregate Formation of Ionic Liquids
Authors: Dorbritz Sandra , Ruth Wolfgang , Kragl Udo 
Published: July 2005

AbstractUnderstanding the behavior of ionic liquids on the molecular level is essential for explaining solubilizing or reaction processes, including catalytic reactions in ionic liquids or with ionic liquids as co‐solvent. Using mass spectrometry techniques it is possible to characterize their aggregate formation behavior, which depends on the used solvent. With increasing polarity of the solvent and decreasing ionic liquid concentration, the size of the formed aggregates decreases. From conductivity measurement curves “critical aggregate concentrations” were calculated, which confirm the results of mass spectrometry measurements. Addition of ionic liquids increases the solubility of acetophenone in water. This effect can be explained by the aggregate formation ability of ionic liquids. The findings can be used to explain the outstanding solubility and solvation properties of ionic liquids.
A High‐Yield, Liquid‐Phase Approach for the Partial Oxidation of Methane to Methanol using SO3 as the Oxidant
Authors: Mukhopadhyay Sudip , Zerella Mark , Bell Alexis T. 
Published: July 2005

AbstractA direct approach for producing methanol from methane in a three‐step, liquid phase process is reported. In the first step, methane is reacted with SO3 to form methanesulfonic acid (MSA) at 75 °C using a free‐radical initiator and MSA as the solvent. Urea‐H2O2 in combination with RhCl3 is found to be the most effective initiator (57% conversion of SO3; 7.2% conversion of CH4). MSA is then oxidized by SO3 at 160 °C in a second step to produce a mixture containing methyl bisulfate and some methyl methanesulfonate (87% conversion of MSA). In the third step, the mixture of methyl bisulfate and methyl methanesulfonate is hydrolyzed in the presence of an organic solvent, to produce an organic phase containing methanol and an aqueous phase containing sulfuric acid and some MSA (63% conversion of methyl bisulfate; 72% conversion of methyl methanesulfonate). Overall, 58% of the MSA (of which 23% is derived from methane) is converted to methanol.
Oxidation of Primary Amines to N‐Monoalkylhydroxylamines using Sodium Tungstate and Hydrogen Peroxide‐Urea Complex
Authors: Heydari Akbar , Aslanzadeh Saied 
Published: July 2005

AbstractThe sodium tungstate‐catalyzed (10 mol %) oxidation of primary amines with a urea‐hydrogen peroxide complex (UHP) gives the corresponding N‐monoalkylhydroxylamines, which are important biologically active compounds, in good to excellent yields. The method is applicable for a wide range of primary amines, including chiral benzylic amines, α‐1,2‐hydroxylamine and α‐amino esters.
Biomimetic Cyclization of Small Terpenoids Promoted by Zeolite NaY: Tandem Formation of α‐Ambrinol from Geranyl Acetone
Authors: Tsangarakis Constantinos , Stratakis Manolis 
Published: July 2005

AbstractZeolite NaY promotes efficiently the biomimetic cyclization of small acyclic terpenes. Geranyl and neryl acetone undergo a novel tandem 1,5‐diene cyclization/carbonyl‐ene reaction to form the natural product α‐ambrinol isolated in >65% yield.
Aqueous Asymmetric Mukaiyama Aldol Reaction Catalyzed by Chiral Gallium Lewis Acid with Trost‐Type Semi‐Crown Ligands
Authors: Li Hui‐Jing , Tian Hong‐Yu , Wu Yan‐Chao , Chen Yong‐Jun , Liu Li , Wang Dong , Li Chao‐Jun 
Published: July 2005

AbstractThe combination of Ga(OTf)3 with chiral semi‐crown ligands (1a–e) generates highly effective chiral gallium Lewis acid catalysts for aqueous asymmetric aldol reactions of aromatic silyl enol ethers with aldehydes. A ligand‐acceleration effect was observed. Water is essential for obtaining high diastereoselectivity and enantioselectivity. The p‐phenyl substituent in aromatic silyl enol ether (2 h) plays an important role and increases the enantioselectivity up to 95% ee. Although aliphatic silyl enol ethers provided low enantioselectivities and silylketene acetal is easily hydrolyzed in aqueous alcohol, the aldol reactions of silylketene thioacetal (12) with aldehydes in the presence of gallium‐Lewis acid catalysts give the β‐hydroxy thioester with reasonable yields and high diastereo‐ (up to 99 : 1) and enantioselectivities (up to 96% ee).
A Convenient High Activity Catalyst for the Sonogashira Coupling of Aryl Bromides
Authors: Köllhofer Axel , Plenio Herbert 
Published: July 2005

AbstractA mixture of Na2PdCl4, CuI and (t‐Bu)3PH+BF4− (molar ratio 4 : 3 : 8) dispersed in H2N(i‐Pr)2+Br− can be used as a “single source” precatalyst for the Sonogashira coupling of aryl bromides with various aryl‐ and alkylacetylenes in HN(i‐Pr)2 solvent. Arylacetylenes require just 0.005 mol % of Pd catalyst at 80 °C, with TOFs ranging between 3,200 and 10,000 h−1.
Bubbling fluidized bed scaling laws: Evaluation at large scales
Authors: Sanderson John , Rhodes Martin 
Published: July 2005

AbstractScaling laws for bubbling fluidized beds were first proposed some two decades ago. Although it would appear that the scaling laws for bubbling beds are for the most part successful, generally experimental verification has been limited to small‐scale equipment. In this paper we apply the simplified scaling laws to a set of four cold‐model bubbling fluidized beds covering a tenfold increase in diameter and perform an experimental verification using an analysis of pressure fluctuations. For pressure fluctuation measurements made at a number of radial and axial locations in all four fluidized beds, an “agreement map” is presented in which the spatial variation in similarity behavior is summarized. Despite a generally good match of results between correctly scaled units, agreement tends to degrade toward the vessel walls and bed surface. At higher gas velocity, pressure fluctuation phenomena observed in the largest bed are not mimicked by smaller units scaled using the simplified criteria. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Mass transfer and chemical reactions in bubble swarms with dynamic interfaces
Authors: Koynov Athanas , Khinast Johannes G. , Tryggvason Grétar 
Published: July 2005

AbstractDetailed, high‐resolution numerical simulations have been performed on the buoyancy‐driven motion of deformable, chemically reacting bubbles for different operating conditions, that is, Weber, Morton, and Schmidt numbers. In our simulations different bubble shapes and types of bubble wakes were observed. The wake types range from a closed wake without recirculation, to a closed wake with recirculation, to an unsteady wake, leading to vortex‐shedding wakes. Two different bubble‐rise trajectories were observed for different conditions: straight and zigzag shaped. The mass‐transfer rates and the yields and selectivities of liquid‐phase chemical reactions were determined for each case. A detailed analysis of the results was carried out, relating the differences in chemical reaction efficiencies to the dynamics of each flow. Furthermore, to obtain a better understanding of the dynamics of the flows inside bubble swarms and their impact on chemical reactions, numerical simulations were performed of multiple bubbles rising in a swarm. Different bubble counts, geometric configurations, and size distributions were considered. Mass‐transfer rates and chemical reaction selectivities were determined and a comparison is presented between the results for bubble swarms and single bubbles. It was shown that for mixing‐sensitive reaction networks, the hydrodynamics of the bubble swarm may significantly impact the reaction selectivity. Furthermore, it was demonstrated that bubble swarm dynamics differ from the dynamics of single bubbles. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Simulated moving‐bed reactor: Reactive–separation regions
Authors: Minceva Mirjana , Rodrigues Alirio E. 
Published: July 2005

AbstractThis work focuses on the design of a simulated moving‐bed rector (SMBR) where reaction A → B + C takes place. The reactive–separation regions were determined for two reactive systems: (1) inversion of sucrose, with enzyme introduced in the unit through the eluent stream and Michaelis–Menten reaction kinetics, and (2) A → B + C reaction, with immobilized enzyme and linear reaction kinetic law. In both systems the reaction species exhibit linear adsorption isotherms. The steady‐state equivalent true moving‐bed reactor (TMBR) analogy was applied in the algorithm used for determination of the reactive–separation regions. The influence of the mass‐transfer limitation, reaction rate, product purities, reactant Henry constant, and SMBR configuration on the shape and position of reactive–separation regions was analyzed. It was shown that in certain conditions the reactive–separation regions extended out of the separation regions obtained for nonreactive SMB for product (B and C) separation. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Experimental and modeling study of protein adsorption in expanded bed
Authors: Li Ping , Xiu Guohua , Rodrigues Alirio E. 
Published: July 2005

AbstractStreamline DEAE is the first‐generation adsorbent developed for expanded bed adsorption (low‐density base matrix with wide particle size distribution and ligand sensitive to ionic strength and salt concentration), and Streamline direct CST I is the second‐generation adsorbent (high‐density base matrix with narrow particle size distribution and ligand not sensitive to ionic strength and salt concentration). In this paper, experiments were carried out for bovine serum albumin (BSA) protein adsorption in expanded beds, where a Streamline 50 column was packed either with Streamline DEAE or with Streamline direct CST I. The hydrodynamics, BSA dynamic binding capacity, and BSA recovery in the whole expanded bed adsorption process were compared for both adsorbents. A mathematical model, in which intraparticle diffusion, film mass transfer, liquid axial dispersion, solid axial dispersion, particle size axial distribution, and bed voidage axial variation were taken into account, was developed to predict the breakthrough curves in expanded bed adsorption. BSA breakthrough curves in expanded bed adsorption were measured for both Streamline DEAE and Streamline CST I, and compared with the predictions from this mathematical model. The effects of intraparticle diffusion, film mass transfer, liquid and solid axial dispersion, particle size axial distribution, and bed voidage axial variation on the breakthrough curves were evaluated for expanded bed adsorption with both adsorbents. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Mesokristalle: anorganische Überstrukturen durch hochparallele Kristallisation und kontrollierte Ausrichtung
Authors: Cölfen Helmut , Antonietti Markus 
Published: July 2005

AbstractKontrollierte Selbstorganisation von Nanopartikeln kann zu neuen Materialien führen; so ist kolloidale Kristallisation von nichtsphärischen Nanokristallen ein Reaktionspfad bei vielen Kristallisationsreaktionen. Mithilfe von Additiven kann die Selbstorganisation auf einer Zwischenstufe – dem Mesokristall – gestoppt werden, bei der die Primäreinheiten noch identifiziert werden können. Solche Mesokristalle wurden bei verschiedenen Systemen als kinetisch metastabile Spezies oder als Intermediat in einer Kristallisationsreaktion beobachtet, die zu Einkristallen mit typischen Defekten und Einschlüssen führt. Über die kontrollierenden Kräfte und den Mechanismus der Mesokristallbildung gibt es noch wenige Erkenntnisse, dagegen sind bereits einige Eigenschaften der Mesokristalle bekannt.Mesokristalle sind spannende Beispiele für nichtklassische Kristallisation, die nicht über Anlagerung von Ionen fortschreitet, sondern über eine modulare Route mit Nanobaueinheiten. Die Kristallisation wird dadurch unabhängiger von Ionenprodukten oder molekularer Löslichkeit und verläuft ohne Änderungen von pH‐Wert oder osmotischem Druck; damit eröffnet die nichtklassische Kristallisation neue Strategien zur Kristallmorphogenese.
Design and utility of a web‐based computer‐assisted instructional tool for neuroanatomy self‐study and review for physical and occupational therapy graduate students
Authors: Foreman K. Bo , Morton David A. , Musolino Gina Maria , Albertine Kurt H. 
Published: July 2005

AbstractThe cadaver continues to be the primary tool to teach human gross anatomy. However, cadavers are not available to students outside of the teaching laboratory. A solution is to make course content available through computer‐assisted instruction (CAI). While CAI is commonly used as an ancillary teaching tool for anatomy, use of screen space, annotations that obscure the image, and restricted interactivity have limited the utility of such teaching tools. To address these limitations, we designed a Web‐based CAI tool that optimizes use of screen space, uses annotations that do not decrease the clarity of the images, and incorporates interactivity across different operating systems and browsers. To assess the design and utility of our CAI tool, we conducted a prospective evaluation of 43 graduate students enrolled in neuroanatomy taught by the Divisions of Physical and Occupational Therapy at the University of Utah, College of Health. A questionnaire addressed navigation, clarity of the images, benefit of the CAI tool, and rating of the CAI tool compared to traditional learning tools. Results showed that 88% of the respondents strongly agreed that the CAI tool was easy to navigate and overall beneficial. Eighty‐four percent strongly agreed that the CAI tool was educational in structure identification and had clear images. Furthermore, 95% of the respondents thought that the CAI tool was much to somewhat better than traditional learning tools. We conclude that the design of a CAI tool, with minimal limitations, provides a useful ancillary tool for human neuroanatomy instruction. Anat Rec (Part B: New Anat) 285B:26–31, 2005. © 2005 Wiley‐Liss, Inc.
Dissection as a teaching tool: Past, present, and future
Authors: Elizondo‐Omaña Rodrigo E. , Guzmán‐López Santos , De Los Angeles García‐Rodríguez María 
Published: July 2005

AbstractCultural changes, scientific progress, and new trends in medical education have modified the role of dissection in teaching anatomy in today's medical schools. We discuss in this article the role of dissection itself, the value of which has been under debate for the last 30 years. The importance of dissection is considered from different points of view: educational, bioethical, and human values. Included are different opinions from professors and students. Finally, the current practice of dissection is described for some universities in the United States and Europe, showing its use as a learning tool. Anat Rec (Part B: New Anat) 285B:11–15, 2005. © 2005 Wiley‐Liss, Inc.
Aerosol delivery of mammalian cells for tissue engineering
Authors: Roberts Andrew , Wyslouzil Barbara E. , Bonassar Lawrence 
Published: July 2005

AbstractWe developed a two fluid atomizer to spray mammalian cells suspended in phosphate buffered saline (PBS)–Pluronic F‐127 polymer solutions. We used the device to spray suspensions of bovine articular chondrocytes and porcine tracheal epithelial cells, in either PBS or the polymer solutions, and studied their viability and growth kinetics. Under the operating conditions examined in this study, the cells had better than 70% viability after spraying, the growth rates were comparable to cells that were not sprayed, and the appearance of the cells at confluence was normal. © 2005 Wiley Periodicals, Inc.
Application of a direct fluorescence‐based live/dead staining combined with fluorescence in situ hybridization for assessment of survival rate of Bacteroides spp. in drinking water
Authors: Savichtcheva Olga , Okayama Noriko , Ito Tsukasa , Okabe Satoshi 
Published: July 2005

AbstractTo evaluate the viability and survival ability of fecal Bacteroides spp. in environmental waters, a fluorescence‐based live/dead staining method using ViaGram™ Red+ Bacterial gram stain and viability kit was combined with fluorescent in situ hybridization (FISH) with 16S rRNA‐targeted oligonucleotide probe (referred as LDS‐FISH). The proposed LDS‐FISH was a direct and reliable method to detect fecal Bacteroides cells and their viability at single‐cell level in complex microbial communities. The pure culture of Bacteroides fragilis and whole human feces were dispersed in aerobic drinking water and incubated at different water temperatures (4°C, 13°C, 18°C, and 24°C), and then the viability of B. fragilis and fecal Bacteroides spp. were determined by applying the LDS‐FISH. The results revealed that temperature and the presence of oxygen have significant effects on the survival ability. Increasing the temperature resulted in a rapid decrease in the viability of both pure cultured B. fragilis cells and fecal Bacteroides spp. The live pure cultured B. fragilis cells could be found at the level of detection in drinking water for 48 h of incubation at 24°C, whereas live fecal Bacteroides spp. could be detected for only 4 h of incubation at 24°C. The proposed LDS‐FISH method should provide useful quantitative information on the presence and viability of Bacteroides spp., a potential alternative fecal indicator, in environmental waters. © 2005 Wiley Periodicals, Inc.
The Prediction of the Absolute Stereochemistry of Primary and Secondary 1,2‐Diols by 1H NMR Spectroscopy: Principles and Applications
Authors: Freire Félix , Seco José M. , Quiñoá Emilio , Riguera Ricardo 
Published: July 2005

AbstractThe absolute configuration of 1,2‐diols formed by a primary and a secondary (chiral) hydroxyl group can be deduced by comparison of the 1H NMR spectra of the corresponding (R)‐ and bis‐(S)‐MPA esters (MPA=methoxyphenylacetic acid). This method involves the use of the chemical shifts of substituents L1/L2 attached to the secondary (chiral) carbon, and of the hydrogen atom linked to the chiral center (CαH) as diagnostic signals. Theoretical (AM1, HF, and B3 LYP calculations) and experimental data (dynamic and low‐temperature NMR spectroscopy, studies on deuterated derivatives, constant coupling analysis, circular dichroism (CD) spectra, and NMR studies with a number of diols of known absolute configuration) prove that the signs of the ΔδRS obtained for those signals correlate with the absolute configuration of the diol. A graphical model for the reliable assignment of the absolute configuration of a 1,2‐diol by comparison of the NMR spectra of its bis‐(R)‐ and bis‐(S)‐MPA esters is presented.
Design, Synthesis, Biological Evaluation and Molecular Docking of Curcumin Analogues as Antioxidant, Cyclooxygenase Inhibitory and Antiinflammatory Agents.
Authors: Selvam C. , Jachak Sanjay M. , Thilagavathi Ramasamy , Chakraborti Asit. K. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Fast and Mild Palladium(II)‐Catalyzed 1,4‐Oxidation of 1,3‐Dienes via Activation of Molecular Oxygen with a Designed Cobalt(II) Porphyrin.
Authors: Verboom Renzo C. , Slagt Vincent F. , Baeckvall Jan‐E. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Selective Allylation of Arenethiols Using Water‐Soluble Palladium Complex Catalyst in Recyclable Water/Hexane Biphasic Media.
Authors: Komine Nobuyuki , Sako Akari , Hirahara Shin‐ya , Hirano Masafumi , Komiya Sanshiro 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Practical Synthesis and Estrogenic Activity of 5‐Hydroxy‐1‐(4′‐hydroxyphenyl)‐1,3,3‐trimethylindan, a Contaminant in Industrial Grade Bisphenol A.
Authors: Terasaki Masanori , Shiraishi Fujio , Nishikawa Tomohiro , Morita Masatoshi , Makino Masakazu 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Regio‐ and Stereoselective Ring Opening of 2,3‐Diaryl Oxiranes by LiBr/Amberlyst 15: A New Stereocontrolled Access to 1,2‐Diaryl‐2‐bromo Alcohols.
Authors: Solladie‐Cavallo Arlette , Lupattelli Paolo , Bonini Carlo 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
One‐Pot Synthesis of β‐Lactams from Aldimines and Ketene Silyl Acetals by Tandem Lewis Base‐Catalyzed Mannich‐Type Addition and Cyclization.
Authors: Takahashi Eiki , Fujisawa Hidehiko , Yanai Toshiharu , Mukaiyama Teruaki 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of 2‐Aryl‐4‐chloropyrroles via Ring Expansion of 2‐Aryl‐1‐chlorocyclopropanecarbaldehydes.
Authors: Verniest Guido , Claessens Sven , Bombeke Filip , Van Thienen Tinneke , De Kimpe Norbert 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Enantioselective Friedel—Crafts Alkylation Reactions Catalyzed by a Chiral Nonracemic C2‐Symmetric 2,2′‐Bipyridyl Copper(II) Complex.
Authors: Lyle Michael P. A. , Draper Neil D. , Wilson Peter D. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of 2‐(3‐Iminoisoindolin‐1‐ylidene)carboxylate Derivatives by Reactions of Ester Magnesium Enolates with Phthalonitrile Derivatives.
Authors: Kobayashi Kazuhiro , Honma Kiyoto , Kondo Shizuka , Morikawa Osamu , Konishi Hisatoshi 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of 2‐Pyrazoline‐5‐carboxylic Acid Derivatives Using Trimethylsilyldiazomethane.
Authors: Ahn Jin Hee , Kim Hye‐Min , Kang Seung Kyu , Ha Jae Du , Yum Eul Kgun , An Duk Keun , Choi Joong‐Kwon , Kim Sung Soo 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Enhancement in Antimicrobial Activity of 2‐(Phenyl)‐3‐(2‐butyl‐4‐chloro‐1H‐imidazolyl)‐5‐butylate Isoxazolidine.
Authors: Sadashiva M. P. , Mallesha H. , Murthy K. Karunakara , Rangappa K. S. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Diastereoselective Amidoalkylation of (3S,7aR)‐6‐Benzyl‐7‐hydroxy‐3‐phenyltetrahydro‐5H‐imidazo[1,5‐c] [1,3]thiazol‐5‐one: A Short and Highly Efficient Synthesis of (+)‐Biotin.
Authors: Chavan Subhash P. , Chittiboyina Amar G. , Ravindranathan T. , Kamat Subhash K. , Kalkote Uttam R. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of 3β,3β,5‐Tribromoacetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one by Bromination of Dehydroacetic Acid.
Authors: Kumar Ajay , Prakash Richa , Singh Shiv P. 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Highly Enantioselective Dynamic Kinetic Resolution and Desymmetrization Processes by Cyclocondensation of Chiral Aminoalcohols with Racemic or Prochiral δ‐Oxoacid Derivatives.
Authors: Amat Mercedes , Bassas Oriol , Pericas Miquel A. , Pasto Mireia , Bosch Joan 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Molybdatophosphoric Acid/NaNO2/Wet SiO2 as an Efficient System for Oxidation of 1,4‐Dihydropyridines under Mild and Heterogeneous Conditions.
Authors: Niknam Khodabakhsh , Zolfigol Mohammah Ali , Razavian Seyed Mehdi , Mohammadpoor‐Baltork Iraj 
Published: July 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.