bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient Synthesis of Dibenzoxaborininols from Diaryl Ethers and Their Application to Dibenzofuran Synthesis
Authors: Niu Liting , Yang Haijun , Jiang Yuyang , Fu Hua 
Published: December 2013

AbstractA convenient and efficient method for the borylation of diaryl ethers leading to dibenzoxaborininols and the synthesis of dibenzofuran derivatives has been developed. The borylation involves the sequential three‐step process: lithiation, borylation and hydrolysis. The synthesized dibenzoxaborininols could be readily transformed into dibenzofuran derivatives in good to excellent yields under palladium catalysis in the presence of iodine, and this is the first example for the formation of an aryl CC bond from diarylborinic acids.magnified image
Palladium Nanoparticles in Glycerol: A Versatile Catalytic System for CX Bond Formation and Hydrogenation Processes
Authors: Chahdoura Faouzi , Pradel Christian , Gómez Montserrat 
Published: December 2013

AbstractPalladium nanoparticles stabilised by tris(3‐sulfophenyl)phosphine trisodium salt in neat glycerol have been synthesised and fully characterised, starting from both Pd(II) and Pd(0) species. The versatility of this innovative catalytic colloidal solution has been proved by its efficient application in CX bond formation processes (X=C, N, P, S) and CC multiple bond hydrogenation reactions. The catalytic glycerol phase could be recycled more than ten times, preserving its activity and selectivity. The scope of each of these processes has demonstrated the power of the as‐prepared catalyst, isolating the corresponding expected products in yields higher than 90%. The dual catalytic behaviour of this glycerol phase, associated to the metallic nanocatalysts used in wet medium (molecular‐ and surface‐like behaviour), has allowed attractive applications in one‐pot multi‐step transformations catalysed by palladium, such as CC coupling followed by hydrogenation, without isolation of intermediates using only one catalytic precursor.magnified image
Oxidative Heck Coupling of Allylic Amines with 2,2,6,6‐Tetramethylpiperidine‐N‐oxyl (TEMPO) as Oxidant for the Preparation of Tetrasubstituted Alkenes
Authors: He Zhiheng , Wibbeling Birgit , Studer Armido 
Published: December 2013

AbstractThe paper describes the oxidative Heck arylation of various allylic amines using arylboronic acids for the preparation of tetrasubstituted alkenes. As oxidant the commercially available 2,2,6,6‐tetramethylpiperidine‐N‐oxyl (TEMPO) is used and coupling reactions occur under very mild conditions at room temperature. The densely substituted alkenes are formed in good to excellent yields with complete control of the diastereoselectivity. Substrate scope with respect to the allylic amine and the arylboronic acid is investigated.magnified image
Highly Efficient Catalytic Dimerization of StyrenesviaCationic Palladium(II) Complexes
Authors: Choi Ji Hye , Kwon Jae Kwan , RajanBabu T. V. , Lim Hwan Jung 
Published: December 2013

AbstractA highly efficient head‐to‐tail dimerization of a styrene was developed using a cationic palladium(II)‐catalyzed selective CC bond forming reaction. The complex [AllylPd(PPh3)]+OTf−, which is believed to generate ‘palladium hydride’ (PdH), catalyzed the dimerization of various styrenes in excellent yields as single isomers. This Pd(II)‐catalyzed reaction provides a new economical CC bond forming method.magnified image
Die Elektrochemie des Sauerstoffs als Meilenstein für eine nachhaltige Energieumwandlung
Authors: Katsounaros Ioannis , Cherevko Serhiy , Zeradjanin Aleksandar R. , Mayrhofer Karl J. J. 
Published: December 2013

AbstractElektrochemie wird eine entscheidende Rolle bei der Einführung von nachhaltigen Lösungen zur Energieversorgung spielen, besonders im Bereich der Umwandlung und Speicherung von elektrischer in chemische Energie in Elektrolysezellen sowie bei der Rückumwandlung und Verwendung der gespeicherten Energie in galvanischen Zellen. Die gemeinsame Herausforderung für beide Prozesse ist die Entwicklung von – bevorzugt leicht verfügbaren – nanostrukturierten Materialien, die diese elektrochemischen Reaktionen mit einem hohen Umsatz und über einen genügend langen Zeitraum katalysieren können. Für die gezielte Entwicklung von Materialien, die diese Voraussetzungen erfüllen, ist es notwendig, die zugrunde liegenden Prozesse und Mechanismen, die unter realen Bedingungen auftreten, vollständig zu verstehen. Eine vielversprechende Strategie, um dieses Verständnis zu erreichen, besteht in der Untersuchung des Einflusses der Materialeigenschaften auf die Aktivität oder Selektivität der Reaktion und die Stabilität unter Anwendungsbedingungen sowie in der Verwendung von komplementären In‐situ‐Techniken zur Untersuchung der Katalysatorstruktur und ‐zusammensetung.
Activation and Retention: A Magnetic Resonance Probe for the Detection of Acute Thrombosis
Authors: Loving Galen S. , Caravan Peter 
Published: December 2013

AbstractBlood‐clot formation that results in the complete occlusion of a blood vessel (thrombosis) often leads to serious life‐threatening events, such as strokes and heart attacks. As the composition of a thrombus changes as it matures, new imaging methods that are capable of distinguishing new clots from old clots may yield important diagnostic and prognostic information. To address this need, an activatable magnetic resonance (MR) probe that is responsive to a key biochemical process associated with recently formed clots has been developed.
Oxygen Electrochemistry as a Cornerstone for Sustainable Energy Conversion
Authors: Katsounaros Ioannis , Cherevko Serhiy , Zeradjanin Aleksandar R. , Mayrhofer Karl J. J. 
Published: December 2013

AbstractElectrochemistry will play a vital role in creating sustainable energy solutions in the future, particularly for the conversion and storage of electrical into chemical energy in electrolysis cells, and the reverse conversion and utilization of the stored energy in galvanic cells. The common challenge in both processes is the development of—preferably abundant—nanostructured materials that can catalyze the electrochemical reactions of interest with a high rate over a sufficiently long period of time. An overall understanding of the related processes and mechanisms occurring under the operation conditions is a necessity for the rational design of materials that meet these requirements. A promising strategy to develop such an understanding is the investigation of the impact of material properties on reaction activity/selectivity and on catalyst stability under the conditions of operation, as well as the application of complementary in situ techniques for the investigation of catalyst structure and composition.
Hydrodynamics of binary mixtures in a tapered gas–solid fluidized bed
Authors: Ren Gang , Pei Pei , Zhang Kai , Wen Dongsheng 
Published: December 2013

ABSTRACTTapered fluidized‐bed reactors are suggested for biomass catalytic pyrolysis in this work. Both experiments and computational fluid dynamics simulations on hydrodynamics are conducted in a two‐dimensional bed with an overall taper angle of 43.8° by using rapeseed as biomass and resin as substitutable catalyst. The results show that the jet penetration depth decreases with increasing initial bed height or decreasing jet gas velocity. However, the jet penetration depth displays a first‐increase and then‐decrease tendency with increasing resin fraction or annular gas velocity. A comparison of hydrodynamics between measured and simulated data, including the stochastic nature of the jets, identifies that the simple non‐viscous two‐fluid model can be used to predict the jet behaviors of both mono‐particle system and well‐mixed biomass mixtures. The results provide fundamental information for the design and scale‐up of tapered fluidized‐bed reactors for solid biomass catalytic pyrolysis. Copyright © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.
Diels–Alder‐based crosslinked self‐healing polyurethane/urea from polymeric methylene diphenyl diisocyanate
Authors: Du Pengfei , Wu Meiyin , Liu Xuanxuan , Zheng Zhen , Wang Xinling , Joncheray Thomas , Zhang Yuefan 
Published: December 2013

ABSTRACTCrosslinked self‐healing polyurethane/urea based on a Diels–Alder reaction (C‐PMPU–DA) was synthesized from a multiple‐furan monomer and a commercial bismaleimide. The multiple‐furan monomer (PMPU–furan) was obtained from a functionalized prepolymer (polymeric MDI: PBA‐2000 = 2:1) by furfuryl amine. The structures of both the PMPU–furan and C‐PMPU–DA were characterized by attenuated total reflectance (ATR)–Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and 1H‐NMR. The Diels–Alder bonds enabled C‐PMPU–DA thermal reversibility, which was investigated by ATR–FTIR spectroscopy, 1H‐NMR, gel–solution–gel experiments, and viscosity tests. Meanwhile, the self‐healing properties of C‐PMPU–DA were also investigated by the recovery of the mechanical properties. The results showed that C‐PMPU–DA exhibited good thermal reversibility and self‐healing properties. C‐PMPU–DA exhibited thermosetting properties at room temperature, although it exhibited thermoplastic properties at higher temperatures and may find applications in self‐healing materials, recyclable materials, or removable materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40234.
Simulation of aerosol effects on orographic clouds and precipitation using WRF model with a detailed bin microphysics scheme
Authors: Xiao Hui , Yin Yan , Jin Lianji , Chen Qian , Chen Jinghua 
Published: December 2013

AbstractThe effects on orographic clouds and precipitation of aerosol loading have been investigated by simulating an idealized mixed‐phase orographic cloud using the Weather Research Forecast (WRF) mesoscale model coupled with a detailed bin microphysics scheme. The results show that the total precipitation amount is reduced by 23.4% with increasing aerosol loading on the orographic clouds. Moreover, increasing aerosol loading will increase the number concentration of cloud droplets in small size range (<19.84 µm in diameter) and lead to a decrease in the peak diameter from 12.5 to 9.92 µm.
The ability of stratospheric climate engineering in stabilizing global mean temperatures and an assessment of possible side effects
Authors: Izrael Yu. A. , Volodin E. M. , Kostrykin S. V. , Revokatova A. P. , Ryaboshapko A. G. 
Published: December 2013

AbstractA coupled atmosphere–ocean general circulation model is used to assess the ability of stratospheric climate engineering (CE) in stabilizing global mean temperatures at the threshold level +2 °C compared to pre‐industrial conditions. CE impact by solar radiation management (SRM) method is applied, when temperature threshold (+2 °C) is reached. Injection intensity is adjusted by the model so that calculated global temperature is remained close to the threshold value. We demonstrate that CE temperature stabilization during the 21st century is possible within the range of +2 ± 0.11 °C. Changes of precipitation intensity as well as effect of sharp termination of CE are investigated.
Atypical teratoid rhabdoid tumor: improved long‐term survival with an intensive multimodal therapy and delayed radiotherapy. The Medical University of Vienna Experience 1992–2012
Authors: Slavc Irene , Chocholous Monika , Leiss Ulrike , Haberler Christine , Peyrl Andreas , Azizi Amedeo A. , Dieckmann Karin , Woehrer Adelheid , Peters Christina , Widhalm Georg , Dorfer Christian , Czech Thomas 
Published: December 2013

AbstractAtypical teratoid rhabdoid tumors (ATRTs) are recently defined highly aggressive embryonal central nervous system tumors with a poor prognosis and no definitive guidelines for treatment. We report on the importance of an initial correct diagnosis and disease‐specific therapy on outcome in 22 consecutive patients and propose a new treatment strategy. From 1992 to 2012, nine patients initially diagnosed correctly as ATRT (cohort A, median age 24 months) were treated according to an intensive multimodal regimen (MUV‐ATRT) consisting of three 9‐week courses of a dose‐dense regimen including doxorubicin, cyclophosphamide, vincristine, ifosfamide, cisplatin, etoposide, and methotrexate augmented with intrathecal therapy, followed by high‐dose chemotherapy (HDCT) and completed with local radiotherapy. Thirteen patients were treated differently (cohort B, median age 30 months) most of whom according to protocols in use for their respective diagnoses. As of July 2013, 5‐year overall survival (OS) and event‐free survival (EFS) for all 22 consecutive patients was 56.3 ± 11.3% and 52.9 ± 11.0%, respectively. For MUV‐ATRT regimen‐treated patients (cohort A) 5‐year OS was 100% and EFS was 88.9 ± 10.5%. For patients treated differently (cohort B) 5‐year OS and EFS were 28.8 ± 13.1%. All nine MUV‐ATRT regimen‐treated patients are alive for a median of 76 months (range: 16–197), eight in first complete remission. Our results compare favorably to previously published data. The drug combination and sequence used in the proposed MUV‐ATRT regimen appear to be efficacious in preventing early relapses also in young children with M1–M3 stage disease allowing postponement of radiotherapy until after HDCT.
Mitsunobu Reactions of 5‐Fluorouridine with the Terpenols Phytol and Nerol: DNA Building Blocks for a Biomimetic Lipophilization of Nucleic Acids
Authors: Malecki Edith , Knies Christine , Werz Emma , Rosemeyer Helmut 
Published: December 2013

AbstractThe cancerostatic 5‐fluorouridine (5‐FUrd; 1) was sequentially sugar‐protected by introduction of a 2′,3′‐O‐heptylidene ketal group (→2), followed by 5′‐O‐monomethoxytritylation (→3). This fully protected derivative was submitted to Mitsunobu reactions with either phytol ((Z and E)‐isomer) or nerol ((Z)‐isomer) to yield the nucleoterpenes 4a and 4b. Both were 5′‐O‐deprotected with 2% Cl2CHCOOH in CH2Cl2 to yield compounds 5a and 5b, respectively. These were converted to the 5′‐O‐cyanoethyl phosphoramidites 6a and 6b, respectively. Moreover, the 2′,3′‐O‐(1‐nonyldecylidene) derivative, 7a, of 5‐fluorouridine was resynthesized and labelled at C(5′) with an Eterneon‐480 fluorophor® (→7b). The resulting nucleolipid was studied with respect to its incorporation in an artificial bilayer, as well as to its aggregate formation. Additionally, two oligonucleotides carrying terminal phytol‐alkylated 5‐fluorouridine tags were prepared, one of which was studied concerning its incorporation in an artificial lipid bilayer.
Catheter approach to redirect hepatic venous return for treatment of unilateral pulmonary arteriovenous malformations after fontan
Authors: Dori Yoav , Sathanandam Shyam , Glatz Andrew C. , Gillespie Matthew J. , Rome Jonathan J. 
Published: December 2013

ObjectivesThe goal of this report is to describe a percutaneous approach to rerouting hepatic venous return in patients who developed progressive cyanosis due to unilateral pulmonary arteriovenous malformations (PAVM) after the total cavopulmonary connection (TCPC) operation.BackgroundUnilateral PAVM can develop in patients after TCPC operation when there is unequal distribution of hepatic venous return between the two lungs. This often results in progressive cyanosis and the need for surgical re‐intervention. A percutaneous based approach for rerouting hepatic venous return has never been described.MethodsWe retrospectively reviewed the clinical data on four patients who underwent percutaneous rerouting procedures. One patient with a misaligned TCPC underwent realignment of the circuit with a bare metal stent. In three patients a combination of bare metal and covered stents were needed to achieve the desired results.ResultsThe rerouting procedures were successful in all patients with significant improvement in oxygen saturation from a median of 75% (range 55–80%) to a median of 90% (range 84–92%) (P = 0.02). There were no recorded short term or intermediate term complications with maximum follow‐up time of 43 months.ConclusionsPercutaneous rerouting of hepatic venous flow is feasible and should be considered when a surgical approach is not possible; this strategy may serve as a viable alternative to complex operative approaches in select cases. Furthermore studies are needed to determine the long‐term efficacy of this procedure. © 2013 Wiley Periodicals, Inc.
Frequency and outcomes of aortocoronary dissection during percutaneous coronary intervention of chronic total occlusions
Authors: Shorrock Deborah , Michael Tesfaldet T. , Patel Vishal , Kotsia Anna , Rangan Bavana V. , Abdullah Shuaib A. , Grodin Jerrold M. , Banerjee Avantika , Brilakis Emmanouil S. 
Published: December 2013

BackgroundAortocoronary dissection can complicate percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs).MethodsWe retrospectively examined the frequency and outcomes of aortocoronary dissection among 336 consecutive CTO PCIs performed at our institution between 2005 and 2012 and performed a systematic review of the published literature.ResultsAortocoronary dissection occurred in six patients (1.8%, 95% confidence intervals 0.7%, 3.8%). All aortocoronary dissections occurred in the right coronary artery (CTO target vessel in five patients and donor vessel in one patient). The baseline clinical characteristics of patients with and without aortocoronary dissection were similar. Compared to patients without, those with aortocoronary dissection were more likely to undergo crossing attempts using the retrograde approach (25% vs. 67%, P = 0.036) and experience a major complication (2.4% vs. 33.3%, P = 0.008). Technical and procedural success rates were similar in both groups. Of the six patients with aortocoronary dissection one underwent emergency coronary bypass graft surgery (CABG), four were treated with ostial stenting, and one was treated conservatively without subsequent adverse clinical outcomes. Systematic literature review provided 107 published cases of aortocoronary dissection during PCI, that occurred mainly in the right coronary artery (74.8%) and were treated with stenting (49.5%), emergency CABG (29%), or conservatively (21.5%).ConclusionsAortocoronary dissection is an infrequent complication of CTO PCI and although it can be treated with stents in most patients, it may infrequently require emergency CABG. © 2013 Wiley Periodicals, Inc.
Pillared Cobalt–Amino Acid Framework Catalysis for Styrene Carbonate Synthesis from CO2 and Epoxide by Metal–Sulfonate–Halide Synergism
Authors: Kathalikkattil Amal Cherian , Roshan Roshith , Tharun Jose , Soek Han‐Geul , Ryu Hyeong‐Seok , Park Dae‐Won 
Published: December 2013

AbstractThe sulfonate anion is proposed as a remarkable partaker in catalyzing epoxide–CO2 cycloaddition for cyclic carbonate synthesis. The role is illustrated by the concerted action of a sulfonate‐rich cobalt–amino acid framework catalyst [{Co(4,4′‐bipy)(L‐cys)(H2O)}⋅H2O]n (2 D‐CCB) and a quaternary ammonium bromide co‐catalyst in synthesizing styrene carbonate (SC) at a turnover number of 228. SC yield at atmospheric pressure is presumed to result from the activation of CO2 by the sulfonate group. The involvement of SO3− anions as basic sites in 2 D‐CCB is ascertained from the initial rate (r0) for catalyzing Knoevenagel condensation reactions and by using CO2 temperature programmed desorption. Microwave pulses are used for synthesizing 2 D‐CCB at a rate that is 288‐fold faster than conventionally employed solvothermal methods. Unambiguous evidence for the pulsating role‐play of sulfonate groups in 2 D‐CCB is perceived by comparing the activity of an analogous metal organic framework (3 D‐CCB) in which the sulfonate oxyanions are jammed by coordination with cobalt. 2 D‐CCB is analyzed for heterogeneity, and reused four times.
Enantioselective Rearrangement Coupled with Water Addition: Direct Synthesis of Enantiomerically Pure Saturated Carboxylic Acids from α,β‐Unsaturated Aldehydes
Authors: Winkler Till , Gröger Harald , Hummel Werner 
Published: December 2013

AbstractA novel type of organic synthesis enabling a direct one‐pot transformation of α,β‐unsaturated aldehydes into saturated carboxylic acids is described. As sole reagent water is required, which is integrated completely in the product. This tandem process proceeds under perfect atom economy, and consists of two coupled redox biotransformations without the need of external co‐substrates for cofactor regeneration. The initial reduction of the CC double bond of an α,β‐unsaturated aldehyde is catalyzed by an NADPH‐dependent ene reductase, leading to the formation of the saturated aldehyde and NADP+. The aldehyde intermediate is then oxidized to the corresponding carboxylic acid, thus regenerating NADPH for the next catalytic cycle. When using prochiral α,β‐unsaturated aldehydes as substrates the corresponding carboxylic acids are formed enantioselectively with up to >99 % ee as demonstrated, e.g., for the transformation of citral to (S)‐citronellic acid.
Quinonediimine‐Induced Oxidative Coupling of Organomagnesium Reagents
Authors: Amaya Toru , Suzuki Riyo , Hirao Toshikazu 
Published: December 2013

AbstractN,N′‐Diphenyl‐p‐benzoquinonediimine, a redox‐active unit of polyaniline, efficiently induced the oxidative homocoupling of various aryl‐ and vinylmagnesium reagents in suppressing the side reactions, such as 1,2‐ or 1,4‐addition reaction.
Dimers of N‐Heterocyclic Carbene Copper, Silver, and Gold Halides: Probing Metallophilic Interactions through Electron Density Based Concepts
Authors: Pinter Balazs , Broeckaert Lies , Turek Jan , Růžička Aleš , De Proft Frank 
Published: December 2013

AbstractHomobimetallic metallophilic interactions between copper, silver, and gold‐based [(NHC)MX]‐type complexes (NHC=N‐heterocyclic carbene, i.e, 1,3,4‐trimethyl‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ylidene; X=F, Cl, Br, I) were investigated by means of ab initio interaction energies, Ziegler–Rauk‐type energy‐decomposition analysis, the natural orbital for chemical valence (NOCV) framework, and the noncovalent interaction (NCI) index. It was found that the dimers of these complexes predominantly adopt a head‐to‐tail arrangement with typical M⋅⋅⋅M distance of 3.04–3.64 Å, in good agreement with the experimental X‐ray structure determined for [{(NHC)AuCl}2], which has an Au⋅⋅⋅Au distance of 3.33 Å. The interaction energies between silver‐ and gold‐based monomers are calculated to be about −25 kcal mol−1, whereas that for the Cu congener is significantly lower (−19.7 kcal mol−1). With the inclusion of thermal and solvent contributions, both of which are destabilizing, by about 15 and 8 kcal mol−1, respectively, an equilibrium process is predicted for the formation of dimer complexes. Energy‐decomposition analysis revealed a dominant electrostatic contribution to the interaction energy, besides significantly stabilizing dispersion and orbital interactions. This electrostatic contribution is rationalized by NHC(δ+)⋅⋅⋅halogen(δ−) interactions between monomers, as demonstrated by electrostatic potentials and derived charges. The dominant NOCV orbital indicates weakening of the π backdonation in the monomers on dimer formation, whereas the second most dominant NOCV represents an electron‐density deformation according to the formation of a very weak M⋅⋅⋅M bond. One of the characteristic signals found in the reduced density gradient versus electron density diagram corresponds to the noncovalent interactions between the metal centers of the monomers in the NCI plots, which is the manifestation of metallophilic interaction.