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Appl. Sci., Volume 2, Issue 1 (March 2012) – 17 articles , Pages 1-244

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599 KiB  
Article
Optimization of Fluorine Plasma Treatment for Interface Improvement on HfO2/In0.53Ga0.47As MOSFETs
by Yen-Ting Chen, Yanzhen Wang, Fei Xue, Fei Zhou and Jack C. Lee
Appl. Sci. 2012, 2(1), 233-244; https://doi.org/10.3390/app2010233 - 19 Mar 2012
Cited by 7 | Viewed by 7569
Abstract
This paper reports significant improvements in the electrical performance of In0.53Ga0.47As metal-oxide-semiconductor field-effect transistors (MOSFET) by a post-gate CF4/O2 plasma treatment. The optimum condition of CF4/O2 plasma treatment has been systematically studied and [...] Read more.
This paper reports significant improvements in the electrical performance of In0.53Ga0.47As metal-oxide-semiconductor field-effect transistors (MOSFET) by a post-gate CF4/O2 plasma treatment. The optimum condition of CF4/O2 plasma treatment has been systematically studied and found to be 30 W for 3–5 min. Approximately 5× reduction in interface trap density from 2.8 × 1012 to 4.9 × 1011 cm−2eV−1 has been demonstrated with fluorine (F) incorporation. Subthreshold swing has been improved from 127 to 109 mV/dec. Effective channel mobility has been enhanced from 826 to 1,144 cm2/Vs. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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574 KiB  
Article
2D Spin-Dependent Diffraction of Electrons From Periodical Chains of Nanomagnets
by Teshome Senbeta and Vadim N. Mal’nev
Appl. Sci. 2012, 2(1), 220-232; https://doi.org/10.3390/app2010220 - 6 Mar 2012
Cited by 1 | Viewed by 5875
Abstract
The scattering of the unpolarized beams of electrons by nanomagnets in the vicinity of some scattering angles leads to complete spin polarized electrons. This result is obtained with the help of the perturbation theory. The dipole-dipole interaction between the magnetic moment of the [...] Read more.
The scattering of the unpolarized beams of electrons by nanomagnets in the vicinity of some scattering angles leads to complete spin polarized electrons. This result is obtained with the help of the perturbation theory. The dipole-dipole interaction between the magnetic moment of the nanomagnet and the magnetic moment of electron is treated as perturbation. This interaction is not spherically symmetric. Rather it depends on the electron spin variables. It in turn results in spinor character of the scattering amplitudes. Due to the smallness of the magnetic interactions, the scattering length of this process is very small to be proved experimentally. To enhance the relevant scattering lengths, we considered the diffraction of unpolarized beams of electrons by linear chains of nanomagnets. By tuning the distance between the scatterers it is possible to obtain the diffraction maximum of the scattered electrons at scattering angles which corresponds to complete spin polarization of electrons. It is shown that the total differential scattering length is proportional to N2 (N is a number of scatterers). Even small number of nanomagnets in the chain helps to obtain experimentally visible enhancement of spin polarization of the scattered electrons. Full article
(This article belongs to the Special Issue Magnetic Nanoparticles: Synthesis, Properties and Applications)
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5398 KiB  
Review
Oxyfluoride Chemistry of Layered Perovskite Compounds
by Yoshihiro Tsujimoto, Kazunari Yamaura and Eiji Takayama-Muromachi
Appl. Sci. 2012, 2(1), 206-219; https://doi.org/10.3390/app2010206 - 6 Mar 2012
Cited by 75 | Viewed by 17793
Abstract
In this paper, we review recent progress and new challenges in the area of oxyfluoride perovskite, especially layered systems including Ruddlesden-Popper (RP), Dion-Jacobson (DJ) and Aurivillius (AV) type perovskite families. It is difficult to synthesize oxyfluoride perovskite using a conventional solid-state reaction because [...] Read more.
In this paper, we review recent progress and new challenges in the area of oxyfluoride perovskite, especially layered systems including Ruddlesden-Popper (RP), Dion-Jacobson (DJ) and Aurivillius (AV) type perovskite families. It is difficult to synthesize oxyfluoride perovskite using a conventional solid-state reaction because of the high chemical stability of the simple fluoride starting materials. Nevertheless, persistent efforts made by solid-state chemists have led to a major breakthrough in stabilizing such a mixed anion system. In particular, it is known that layered perovskite compounds exhibit a rich variety of O/F site occupation according to the synthesis used. We also present the synthetic strategies to further extend RP type perovskite compounds, with particular reference to newly synthesized oxyfluorides, Sr2CoO3F and Sr3Fe2O5+xF2−x (x ~ 0.44). Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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1918 KiB  
Article
Stain Resistance of Cotton Fabrics before and after Finishing with Admicellar Polymerization
by Srinivas Hanumansetty, Jayanta Maity, Rod Foster and Edgar A. O’Rear
Appl. Sci. 2012, 2(1), 192-205; https://doi.org/10.3390/app2010192 - 5 Mar 2012
Cited by 18 | Viewed by 9537
Abstract
Environmental concerns related to perfluoroctanoic acid (PFOA) led to a re-examination of the methods for imparting stain resistance and stain repellency to textiles. Non-PFOA fluoropolymer finishes have been formed on cotton knits by admicellar polymerization, a surface analogue of emulsion polymerization. Fabric samples [...] Read more.
Environmental concerns related to perfluoroctanoic acid (PFOA) led to a re-examination of the methods for imparting stain resistance and stain repellency to textiles. Non-PFOA fluoropolymer finishes have been formed on cotton knits by admicellar polymerization, a surface analogue of emulsion polymerization. Fabric samples were characterized by a drop test, contact angle measurements, SEM, elemental analysis and durability studies. Stain resistance and stain release properties were assessed by reflectance and AATCC tests with results comparing favorably with swatches from commercially available garments. Admicellar polymerization enabled the formation of durable finishes that exhibited high performance in stain resistance and stain repellency. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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1655 KiB  
Article
Self-Assembled Fluorinated Organogelators for Surface Modification
by Anilkumar Raghavanpillai and Vincent A. Franco
Appl. Sci. 2012, 2(1), 175-191; https://doi.org/10.3390/app2010175 - 1 Mar 2012
Cited by 11 | Viewed by 8022
Abstract
A new class of alkyl- and perfluoroalkyl-containing urea and amide derivatives was synthesized from amino acid derivatives. Most of these compounds showed excellent gelation behavior in organic solvents at low concentrations. A few organogelators selected from the initial screening were used for surface [...] Read more.
A new class of alkyl- and perfluoroalkyl-containing urea and amide derivatives was synthesized from amino acid derivatives. Most of these compounds showed excellent gelation behavior in organic solvents at low concentrations. A few organogelators selected from the initial screening were used for surface modification of fibrous substrates to create hydrophobic and oleophobic composites. The hydrophobic and oleophobic behaviors of these composites were ascribed to a combination of increased surface roughness and the alkyl/fluorinated functionalities present in the gelator backbone. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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539 KiB  
Article
Reduction and Immobilization of Potassium Permanganate on Iron Oxide Catalyst by Fluidized-Bed Crystallization Technology
by Guang-Xia Li, Yao-Hui Huaug, Teng-Chien Chen, Yu-Jen Shih and Hui Zhang
Appl. Sci. 2012, 2(1), 166-174; https://doi.org/10.3390/app2010166 - 1 Mar 2012
Cited by 10 | Viewed by 9731
Abstract
A manganese immobilization technology in a fluidized-bed reactor (FBR) was developed by using a waste iron oxide (i.e., BT-3) as catalyst which is a by-product from the fluidized-bed Fenton reaction (FBR-Fenton). It was found that BT-3 could easily reduce potassium permanganate [...] Read more.
A manganese immobilization technology in a fluidized-bed reactor (FBR) was developed by using a waste iron oxide (i.e., BT-3) as catalyst which is a by-product from the fluidized-bed Fenton reaction (FBR-Fenton). It was found that BT-3 could easily reduce potassium permanganate (KMnO4) to MnO2. Furthermore, MnO2 could accumulate on the surface of BT-3 catalyst to form a new Fe-Mn oxide. Laboratory experiments were carried out to investigate the KMnO4-reduction mechanism, including the effect of KMnO4 concentration, BT-3 dosage, and operational solution pH. The results showed that the pH solution was a significant factor in the reduction of KMnO4. At the optimum level, pHf 6, KMnO4 was virtually reduced in 10 min. A pseudo-first order reaction was employed to describe the reduction rate of KMnO4. Full article
(This article belongs to the Special Issue Feature Papers)
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285 KiB  
Article
Scaling Law for Photon Transmission through Optically Turbid Slabs Based on Random Walk Theory
by Xuesong Li and Lin Ma
Appl. Sci. 2012, 2(1), 160-165; https://doi.org/10.3390/app2010160 - 1 Mar 2012
Cited by 8 | Viewed by 6565
Abstract
Past work has demonstrated the value of a random walk theory (RWT) to solve multiple-scattering problems arising in numerous contexts. This paper’s goal is to investigate the application range of the RWT using Monte Carlo simulations and extending it to anisotropic media using [...] Read more.
Past work has demonstrated the value of a random walk theory (RWT) to solve multiple-scattering problems arising in numerous contexts. This paper’s goal is to investigate the application range of the RWT using Monte Carlo simulations and extending it to anisotropic media using scaling laws. Meanwhile, this paper also reiterates rules for converting RWT formulas to real physical dimensions, and corrects some errors which appear in an earlier publication. The RWT theory, validated by the Monte Carlo simulations and combined with the scaling law, is expected to be useful to study multiple scattering and to greatly reduce the computation cost. Full article
(This article belongs to the Special Issue Feature Papers)
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1555 KiB  
Article
Real-Time PCR Data Processing Shown by the Analysis of Colorectal Specific Candidate Genes, ERCC1, RRM1 and TS in Relation to β2M as Endogenous Control
by Melanie Demes, Holger Bartsch, Stefanie Scheil-Bertram, Ralph Mücke and Annette Fisseler-Eckhoff
Appl. Sci. 2012, 2(1), 139-159; https://doi.org/10.3390/app2010139 - 24 Feb 2012
Cited by 10 | Viewed by 9235
Abstract
Currently, quantitative real-time PCR (Q-PCR) of archival formalin-fixed, paraffin embedded (FFPE) tissue is a critical tool for research and is not well established in routine diagnostics. Therefore, continuous improvement in mathematics and statistics associated with interpreting final accurate and reproducible results are fundamental. [...] Read more.
Currently, quantitative real-time PCR (Q-PCR) of archival formalin-fixed, paraffin embedded (FFPE) tissue is a critical tool for research and is not well established in routine diagnostics. Therefore, continuous improvement in mathematics and statistics associated with interpreting final accurate and reproducible results are fundamental. This project describes and discusses specificity and sensitivity with respect to intra- and inter-assay variances by use of a commercial Human Reference RNA and individual RNA derived from colorectal cancer patients (n = 25). All patients were treated with 5-fluoruracil (5-FU) and a concomitant pelvic radiotherapy (50.4 Gy). Quality assessment of target tissue samples was evaluated by clinicopathological findings and optical density (OD) measurements. We analyzed the steady state messenger RNA (mRNA) expression level of a small panel of cancer relevant genes, excision repair cross-complementing group 1 (ERCC1), ribonucleoside-diphosphate reductase subunit M1 (RRM1), thymidylate synthase (TYMS) and ß-2microglobulin (ß-2M) as endogenous control. The mRNA of a Human Reference RNA, tumor and non-neoplastic material was reverse transcribed into its complementary DNA (cDNA). cDNA was amplified based on dual-labeled TaqMan real-time fluorescence measurements. The real-time efficiency and therefore the output data can be influenced through the kind of calibrator used, the amount and quality of used RNA and by the degree of individual assay variability. Each sample presents an individual amplification curve. Thus, confirmation of primer specificity, one or more invariant endogenous controls, RNA and cDNA quality, as well as real-time PCR amplification efficiencies and linearity calculations from individual slopes or R2-values must be included in each study. Full article
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346 KiB  
Article
Computational Study on the Acid Catalyzed Reactions of Fluorine-Containing 2,4-Dialkoxy-3,4-dihydro-2H-pyrans with Aromatic Compounds
by Norio Ota, Yasuhiro Kamitori, Ryusuke Shirai, Mizuki Hatakenaka and Etsuji Okada
Appl. Sci. 2012, 2(1), 129-138; https://doi.org/10.3390/app2010129 - 24 Feb 2012
Cited by 3 | Viewed by 7082
Abstract
The reaction of 2,4-diethoxy-6-trifluoromethyl-3,4-dihydro-2H-pyran (1) with aromatic compounds in refluxing acetonitrile in the presence of p-toluenesulfonic acid gave the mixture of 4-aryl-2-trifluoromethyl-4H-pyrans (3) and 6-aryl-1,1,1-trifluorohexa-3,5-dien-2-ones (4). In contrast, the same reaction carried [...] Read more.
The reaction of 2,4-diethoxy-6-trifluoromethyl-3,4-dihydro-2H-pyran (1) with aromatic compounds in refluxing acetonitrile in the presence of p-toluenesulfonic acid gave the mixture of 4-aryl-2-trifluoromethyl-4H-pyrans (3) and 6-aryl-1,1,1-trifluorohexa-3,5-dien-2-ones (4). In contrast, the same reaction carried out in trifluoroacetic acid at ambient temperature afforded 4-aryl-2-ethoxy-6-trifluoromethyl-3,4-dihydro-2H-pyrans (2) selectively. These two types of reactions giving quite different products under each condition were studied on the basis of DFT calculations. Moreover, the proposed mechanism for the reaction of 5-trifluoroacetyl-6-trifluoromethyl-3,4-dihydro-2H-pyran (5) with aromatic compounds affording butadiene derivatives (6) exclusively was also discussed based on the calculations and comparison with the reactivity of pyrylium intermediate (7). Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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391 KiB  
Article
A Study of Fluorinated β-Nitrostyrenes as Antimicrobial Agents
by King Lo, Hugh Cornell, Gina Nicoletti, Neale Jackson and Helmut Hügel
Appl. Sci. 2012, 2(1), 114-128; https://doi.org/10.3390/app2010114 - 23 Feb 2012
Cited by 18 | Viewed by 7134
Abstract
The effect of variously fluorine-substituted β-methyl-β-nitrostyrenes on their antimicrobial activity was investigated. Their efficacy was determined by minimum inhibition concentration (MIC) in cultures of Gram positive and Gram negative bacteria and a fungus. Highest activity against the Gram negative bacterium, E.coli, was [...] Read more.
The effect of variously fluorine-substituted β-methyl-β-nitrostyrenes on their antimicrobial activity was investigated. Their efficacy was determined by minimum inhibition concentration (MIC) in cultures of Gram positive and Gram negative bacteria and a fungus. Highest activity against the Gram negative bacterium, E.coli, was achieved with 4-fluorine-aryl substituted β-methyl-β-nitrostyrenes, while most compounds gave excellent results against gram positive bacteria. Importantly, the addition of the β-methyl group profoundly enhanced the antibacterial activity of the compounds tested. The comparative KD values for the most potent compounds against E.coli were much lower than those required for the gram positive and fungus counterparts. This investigation illustrated that fluorine substituted nitropropenylarenes have enhanced antimicrobial activity suitable for antibiotic applications. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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847 KiB  
Article
The Logic-Based Supervisor Control for Sun-Tracking System of 1 MW HCPV Demo Plant: Study Case
by Hong-Yih Yeh and Cheng-Dar Lee
Appl. Sci. 2012, 2(1), 100-113; https://doi.org/10.3390/app2010100 - 7 Feb 2012
Cited by 6 | Viewed by 5995
Abstract
This paper presents a logic-based supervisor controller designed for trackers for a 1MW HCPV demo plant in Taiwan. A sun position sensor on the tracker is used to detect the sun position, as the sensor is sensitive to the intensity of sun light. [...] Read more.
This paper presents a logic-based supervisor controller designed for trackers for a 1MW HCPV demo plant in Taiwan. A sun position sensor on the tracker is used to detect the sun position, as the sensor is sensitive to the intensity of sun light. The signal output of the sensor is partially affected by the cloud, which has a hard control position with the traditional PID control. Therefore we have used logic-based supervisor (LBS) control which permits switching the PID control to sun trajectory under sunny or cloudy conditions. To verify the stability of the proposed control, an experiment was performed and the results show that the proposed control can efficiently achieve stabilization of the trackers of the 1MW HCPV demo plant. Full article
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645 KiB  
Article
Novel Fluorinated Indanone, Tetralone and Naphthone Derivatives: Synthesis and Unique Structural Features
by Joseph C. Sloop, Paul D. Boyle, Augustus W. Fountain, Cristina Gomez, James L. Jackson, William F. Pearman, Robert D. Schmidt and Jonathan Weyand
Appl. Sci. 2012, 2(1), 61-99; https://doi.org/10.3390/app2010061 - 1 Feb 2012
Cited by 7 | Viewed by 9197
Abstract
Several fluorinated and trifluoromethylated indanone, tetralone and naphthone derivatives have been prepared via Claisen condensations and selective fluorinations in yields ranging from 22–60%. In addition, we report the synthesis of new, selectively fluorinated bindones in yields ranging from 72–92%. Of particular interest is [...] Read more.
Several fluorinated and trifluoromethylated indanone, tetralone and naphthone derivatives have been prepared via Claisen condensations and selective fluorinations in yields ranging from 22–60%. In addition, we report the synthesis of new, selectively fluorinated bindones in yields ranging from 72–92%. Of particular interest is the fluorination and trifluoroacetylation regiochemistry observed in these fluorinated products. We also note unusual transformations including a novel one pot, dual trifluoroacetylation, trifluoroacetylnaphthone synthesis via a deacetylation as well as an acetyl-trifluoroacetyl group exchange. Solid-state structural features exhibited by these compounds were investigated using crystallographic methods. Crystallographic results, supported by spectroscopic data, show that trifluoroacetylated ketones prefer a chelated cis-enol form whereas fluorinated bindone products exist primarily as the cross-conjugated triketo form. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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357 KiB  
Review
Enhancement of Brillouin Scattering Signal in Perfluorinated Graded-Index Polymer Optical Fibers
by Yosuke Mizuno and Kentaro Nakamura
Appl. Sci. 2012, 2(1), 46-60; https://doi.org/10.3390/app2010046 - 31 Jan 2012
Cited by 3 | Viewed by 7558
Abstract
Perfluorinated graded-index polymer optical fibers (PFGI-POFs), fabricated by replacing the hydrogen atoms of standard polymethyl methacrylate-based POFs with fluorine atoms, have been extensively studied due to their relatively low propagation loss even at telecommunication wavelength. Recently, Brillouin scattering, which is one of the [...] Read more.
Perfluorinated graded-index polymer optical fibers (PFGI-POFs), fabricated by replacing the hydrogen atoms of standard polymethyl methacrylate-based POFs with fluorine atoms, have been extensively studied due to their relatively low propagation loss even at telecommunication wavelength. Recently, Brillouin scattering, which is one of the most significant nonlinear effects in optical fibers, has been successfully observed in PFGI-POFs at 1.55-μm wavelength. The Brillouin Stokes signal was, however, not large enough for practical applications or for detailed investigations of the Brillouin properties. In this paper, we review our recent work on Stokes signal enhancement. First, we induce stimulated Brillouin scattering based on the so-called pump-probe technique, and discuss its applicability to temperature sensors. Then, we investigate the influence of the core diameter and length of PFGI-POFs on Stokes signal, and observe the Brillouin linewidth narrowing effect. We believe our work is an important technological step toward the implementation of practical Brillouin-based devices and systems including distributed strain and temperature sensors. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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0 pages, 385 KiB  
Article
RETRACTED: Steady State Analytical Equation of Motion of Linear Shaped Charges Jet Based on the Modification of Birkhoff Theory
by Seokbin Lim
Appl. Sci. 2012, 2(1), 35-45; https://doi.org/10.3390/app2010035 - 31 Jan 2012
Cited by 11 | Viewed by 8924 | Retraction
Abstract
Birkhoff theory exhibits an analytical steady state liner collapse model of shaped charges followed by jetting process. It also provides the fundamental idea in study of shaped charges and has widened its application in many areas, including a configuration where the detonation front [...] Read more.
Birkhoff theory exhibits an analytical steady state liner collapse model of shaped charges followed by jetting process. It also provides the fundamental idea in study of shaped charges and has widened its application in many areas, including a configuration where the detonation front strikes the entire liner surface at the same time providing the α = β (liner apex angle α, and the liner collapse point angle β) condition in the literature. Upon consideration of the detonation front propagation along the lateral length of the core charge in LSCs (linear shaped charges), a further modification of the Birkhoff theory motivated by the unique geometrical condition of LSCs and the α = β condition is necessary to correctly describe the jetting behavior of LSCs which is different than that of CSCs (conical shaped charges). Based on such unique geometrical properties of LSCs, the original Birkhoff theory was modified and an analytical steady state LSCs model was built. The analytical model was then compared to the numerical simulation results created from Autodyn™ in terms of M/C ratio and apex angles in three different sized LSCs, and it exhibits favorable results in a limited range. Full article
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682 KiB  
Article
Nanoimprint Resist Material Containing Ultraviolet Reactive Fluorine Surfactant for Defect Reduction in Lithographic Fabrication
by Satoshi Takei and Atsushi Sekiguchi
Appl. Sci. 2012, 2(1), 24-34; https://doi.org/10.3390/app2010024 - 16 Jan 2012
Cited by 16 | Viewed by 7516
Abstract
The generated resist based defects on the template in addition to the presence of particles and contaminants is critical for ultraviolet curing of nanoimprint lithographic fabrication. This procedure is proven to be suitable for advanced resist material design under the process conditions. Nanoimprint [...] Read more.
The generated resist based defects on the template in addition to the presence of particles and contaminants is critical for ultraviolet curing of nanoimprint lithographic fabrication. This procedure is proven to be suitable for advanced resist material design under the process conditions. Nanoimprint resist material containing an ultraviolet reactive fluorine surfactant was developed to modify the fundamental surface interactions between resists and the template for defect reduction in nanoimprint patterning replication. The developed acrylate type nanoimprint resist material containing 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoro-2-hydroxyundecyl acrylate as an ultraviolet reactive fluorine surfactant, indicated excellent patterning dimensional accuracy by minimizing surface free energy, and having the effect of improving the generated resist based defect numbers on the template, with a 500 nm contact hole and 2 μm line patterns, in the replication of 20 nanoimprint process cycles. This desirable concept using an ultraviolet reactive fluorine surfactant with an acrylate group in the acrylate type nanoimprint resist material is one of the most promising processes ready to be incorporated into mass fabrication in the next generation of electronic devices. Full article
(This article belongs to the Special Issue Organo-Fluorine Chemical Science)
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103 KiB  
Article
Surface Sampling of a Dry Aerosol Deposited Ricin
by Jason M. Edmonds, Patricia J. Collett, Rebecca L. Brown and Kishna Mangaya
Appl. Sci. 2012, 2(1), 13-23; https://doi.org/10.3390/app2010013 - 13 Jan 2012
Cited by 1 | Viewed by 6694
Abstract
Sampling of small molecules from both porous and non-porous surfaces poses a significant challenge across biological agents. Particle sizes of toxins are smaller than living organisms and can be extremely toxic at low level concentrations. A small number of studies evaluating sampling efficiencies [...] Read more.
Sampling of small molecules from both porous and non-porous surfaces poses a significant challenge across biological agents. Particle sizes of toxins are smaller than living organisms and can be extremely toxic at low level concentrations. A small number of studies evaluating sampling efficiencies of commercial off the shelf (COTS) materials have been performed with toxins and proteins. However, they have been limited to non-ricin stimulants with drastically different physical properties than their native counterparts. We have identified a commercially available non-toxic recombinant ricin, complete with both A and B subunits present, which can be recognized by antibodies commonly used to assay native ricin. In evaluating recovery efficiency, we deposited the recombinant ricin by both liquid deposition, and as a dry aerosol. Our studies demonstrated a significant difference in recovery efficiencies from liquid deposited ricin, ranging between 30% and 70%, than from an aerosol generated deposition ranging from below detectable levels to 22%, depending on the contaminated surface and swab material being used. This study demonstrates the necessity for accurate dissemination techniques of sampling technologies for the consideration of use in an environment where suspected toxin contamination is being evaluated. Full article
(This article belongs to the Special Issue Feature Papers)
270 KiB  
Communication
Chiral β-Amino Alcohols as Ligands for the Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation of N-Phosphinyl Ketimines
by Óscar Pablo, David Guijarro and Miguel Yus
Appl. Sci. 2012, 2(1), 1-12; https://doi.org/10.3390/app2010001 - 9 Jan 2012
Cited by 8 | Viewed by 7561
Abstract
Some chiral β-amino alcohols have been evaluated as potential ligands for the ruthenium-catalyzed asymmetric transfer hydrogenation (ATH) of N-phosphinyl ketimines in isopropyl alcohol. The ruthenium complex prepared from [RuCl2(p-cymene)]2 and (1S,2R)-1-amino-2-indanol has shown [...] Read more.
Some chiral β-amino alcohols have been evaluated as potential ligands for the ruthenium-catalyzed asymmetric transfer hydrogenation (ATH) of N-phosphinyl ketimines in isopropyl alcohol. The ruthenium complex prepared from [RuCl2(p-cymene)]2 and (1S,2R)-1-amino-2-indanol has shown to be an efficient catalyst for the ATH of several N-(diphenylphosphinyl)imines, affording the reduction products in very good isolated yields and enantiomeric excesses up to 82%. The inherent rigidity of the indane ring system present in the ligand seems to be very important to achieve good enantioselectivities. Full article
(This article belongs to the Special Issue Feature Papers)
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