The Experts below are selected from a list of 1974 Experts worldwide ranked by ideXlab platform
Lei Tang - One of the best experts on this subject based on the ideXlab platform.
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high strength hydrogels with integrated functions of h bonding and thermoresponsive surface mediated reverse transfection and cell detachment
Advanced Materials, 2010Co-Authors: Lei TangAbstract:1. Materials: 2-Vinyl-4,6-diamino-1,3,5-triazine (VDT, Tokyo Kasei Kogyo), Nisopropylacrylamide, (NIPAAm, 97%, Aldrich), polyethylene glycol diacrylate (PEGDA, Mn = 575, Aldrich) and 2-hydroxy-4-(2-hydroxyethoxy)-2-methyl -Propiophenone, (IRGACURE2959, 98%, Aldrich) were used as received. Plasmid pGL3-control (encoding luciferase reporter gene, 5256bp, Promega) was prepared by Plasmid Rapid Isolation Kit (BioDev, Beijing, China). Dimeric cyanine dye YOYO-1 iodide was purchased from Molecular Probes, USA. All other chemicals were analytical grade.
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High‐Strength Hydrogels with Integrated Functions of H‐bonding and Thermoresponsive Surface‐Mediated Reverse Transfection and Cell Detachment
Advanced materials (Deerfield Beach Fla.), 2010Co-Authors: Lei Tang, Wenguang Liu, Guipei LiuAbstract:1. Materials: 2-Vinyl-4,6-diamino-1,3,5-triazine (VDT, Tokyo Kasei Kogyo), Nisopropylacrylamide, (NIPAAm, 97%, Aldrich), polyethylene glycol diacrylate (PEGDA, Mn = 575, Aldrich) and 2-hydroxy-4-(2-hydroxyethoxy)-2-methyl -Propiophenone, (IRGACURE2959, 98%, Aldrich) were used as received. Plasmid pGL3-control (encoding luciferase reporter gene, 5256bp, Promega) was prepared by Plasmid Rapid Isolation Kit (BioDev, Beijing, China). Dimeric cyanine dye YOYO-1 iodide was purchased from Molecular Probes, USA. All other chemicals were analytical grade.
Frank Prechtl - One of the best experts on this subject based on the ideXlab platform.
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enantioselective oxidation of chiral titanium enolates derived from Propiophenone by dimethyldioxirane or 3 phenyl 2 phenylsulfonyloxazirdine
Chemische Berichte, 1994Co-Authors: Waldemar Adam, Frank PrechtlAbstract:The stereoselective oxidation of the optically active titanium enolate complexes 2 of Propiophenone by dimethyldioxirane (3) (as acetone solution) and 3-phenyl-2-phenylsulfonyloxaziridine (4) has been investigated. The chiral titanium enolates 2 were synthesized by the reaction of the lithium enolate of Propiophenone and the respective optically active chlorotitanate complexes 1. For 3 as oxidant, the stereoselectivity of the a hydroxylation strongly depends on the substitution pattern at the central titanium atom and reached for the best case, namely 2e, an enantiometric excess (ee) of 63%. Solvent and temperature exhibited only small effects on the stereoselectivity. Compound 4 as oxidant gave lower enantiomeric excesses than 3
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Enantioselective Oxidation of Chiral Titanium Enolates Derived from Propiophenone by Dimethyldioxirane or 3‐Phenyl‐2‐phenylsulfonyloxazirdine
Chemische Berichte, 1994Co-Authors: Waldemar Adam, Frank PrechtlAbstract:The stereoselective oxidation of the optically active titanium enolate complexes 2 of Propiophenone by dimethyldioxirane (3) (as acetone solution) and 3-phenyl-2-phenylsulfonyloxaziridine (4) has been investigated. The chiral titanium enolates 2 were synthesized by the reaction of the lithium enolate of Propiophenone and the respective optically active chlorotitanate complexes 1. For 3 as oxidant, the stereoselectivity of the a hydroxylation strongly depends on the substitution pattern at the central titanium atom and reached for the best case, namely 2e, an enantiometric excess (ee) of 63%. Solvent and temperature exhibited only small effects on the stereoselectivity. Compound 4 as oxidant gave lower enantiomeric excesses than 3
Waldemar Adam - One of the best experts on this subject based on the ideXlab platform.
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enantioselective oxidation of chiral titanium enolates derived from Propiophenone by dimethyldioxirane or 3 phenyl 2 phenylsulfonyloxazirdine
Chemische Berichte, 1994Co-Authors: Waldemar Adam, Frank PrechtlAbstract:The stereoselective oxidation of the optically active titanium enolate complexes 2 of Propiophenone by dimethyldioxirane (3) (as acetone solution) and 3-phenyl-2-phenylsulfonyloxaziridine (4) has been investigated. The chiral titanium enolates 2 were synthesized by the reaction of the lithium enolate of Propiophenone and the respective optically active chlorotitanate complexes 1. For 3 as oxidant, the stereoselectivity of the a hydroxylation strongly depends on the substitution pattern at the central titanium atom and reached for the best case, namely 2e, an enantiometric excess (ee) of 63%. Solvent and temperature exhibited only small effects on the stereoselectivity. Compound 4 as oxidant gave lower enantiomeric excesses than 3
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Enantioselective Oxidation of Chiral Titanium Enolates Derived from Propiophenone by Dimethyldioxirane or 3‐Phenyl‐2‐phenylsulfonyloxazirdine
Chemische Berichte, 1994Co-Authors: Waldemar Adam, Frank PrechtlAbstract:The stereoselective oxidation of the optically active titanium enolate complexes 2 of Propiophenone by dimethyldioxirane (3) (as acetone solution) and 3-phenyl-2-phenylsulfonyloxaziridine (4) has been investigated. The chiral titanium enolates 2 were synthesized by the reaction of the lithium enolate of Propiophenone and the respective optically active chlorotitanate complexes 1. For 3 as oxidant, the stereoselectivity of the a hydroxylation strongly depends on the substitution pattern at the central titanium atom and reached for the best case, namely 2e, an enantiometric excess (ee) of 63%. Solvent and temperature exhibited only small effects on the stereoselectivity. Compound 4 as oxidant gave lower enantiomeric excesses than 3
P. R. Sowbna - One of the best experts on this subject based on the ideXlab platform.
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Selectivity Engineering in Synthesis of 4-Benzyloxy Propiophenone Using Liquid–Liquid–Liquid Phase-Transfer Catalysis
Industrial & Engineering Chemistry Research, 2012Co-Authors: Ganapati D. Yadav, P. R. SowbnaAbstract:4-Benzyloxy Propiophenone is an important active pharmaceutical intermediate (API) used in the production of drugs such as Ifenprodil (N-methyl-d-aspartate receptor antagonist) and Buphenine (or nylidrin, a sympathomimetic and beta-adrenergic agonist). The synthesis of this molecule involves cumbersome and highly polluting routes. In the current work, synthesis of 4-benzyloxy Propiophenone was achieved by reacting benzyl chloride with 4-hydroxy Propiophenone and sodium hydroxide in liquid–liquid–liquid (L-L-L) phase-transfer catalysis (PTC) with tetra butyl ammonium bromide (TBAB) as the catalyst. The novelty of the L-L-L PTC over L-L PTC is that the catalyst forms a separate phase and can be separated easily and reused several times. L-L-L PTC intensifies the rates of reaction and is 100% selective toward 4-benzyloxy Propiophenone. Thus, the goal of green chemistry—waste minimization—was achieved. The effects of various parameters on the rate of reaction were studied. A mechanistic model was proposed to ...
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selectivity engineering in synthesis of 4 benzyloxy Propiophenone using liquid liquid liquid phase transfer catalysis
Industrial & Engineering Chemistry Research, 2012Co-Authors: Ganapati D. Yadav, P. R. SowbnaAbstract:4-Benzyloxy Propiophenone is an important active pharmaceutical intermediate (API) used in the production of drugs such as Ifenprodil (N-methyl-d-aspartate receptor antagonist) and Buphenine (or nylidrin, a sympathomimetic and beta-adrenergic agonist). The synthesis of this molecule involves cumbersome and highly polluting routes. In the current work, synthesis of 4-benzyloxy Propiophenone was achieved by reacting benzyl chloride with 4-hydroxy Propiophenone and sodium hydroxide in liquid–liquid–liquid (L-L-L) phase-transfer catalysis (PTC) with tetra butyl ammonium bromide (TBAB) as the catalyst. The novelty of the L-L-L PTC over L-L PTC is that the catalyst forms a separate phase and can be separated easily and reused several times. L-L-L PTC intensifies the rates of reaction and is 100% selective toward 4-benzyloxy Propiophenone. Thus, the goal of green chemistry—waste minimization—was achieved. The effects of various parameters on the rate of reaction were studied. A mechanistic model was proposed to ...
J. Linek - One of the best experts on this subject based on the ideXlab platform.
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excess molar volumes of Propiophenone toluene and estimated density of liquid Propiophenone below its melting temperature
The Journal of Chemical Thermodynamics, 2006Co-Authors: L. Morávková, J. LinekAbstract:Abstract The densities of liquid Propiophenone and toluene, and of their mixtures were measured at six temperatures between 283.15 K, and 328.15 K by means of a vibrating-tube densimeter. The excess molar volumes V m E calculated from the density data show that the deviations from ideal behaviour in the systems studied (all being negative) become more negative as the temperature is raised. The V m E results were correlated using the fourth-order Redlich–Kister equation, with the maximum likelihood principle being applied for the determination of the adjustable parameters. The density values of liquid Propiophenone at 283.15 K and 288.15 K (below its melting temperature equal 291.76 K) needed for the computation of V m E were determined both from the extrapolation of densities measured at higher temperatures and from excess volume correlation using the respective density value as an adjustable parameter. Both the estimation methods are compared and discussed.
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Excess molar volumes of (Propiophenone + toluene) and estimated density of liquid Propiophenone below its melting temperature
The Journal of Chemical Thermodynamics, 2006Co-Authors: L. Morávková, J. LinekAbstract:Abstract The densities of liquid Propiophenone and toluene, and of their mixtures were measured at six temperatures between 283.15 K, and 328.15 K by means of a vibrating-tube densimeter. The excess molar volumes V m E calculated from the density data show that the deviations from ideal behaviour in the systems studied (all being negative) become more negative as the temperature is raised. The V m E results were correlated using the fourth-order Redlich–Kister equation, with the maximum likelihood principle being applied for the determination of the adjustable parameters. The density values of liquid Propiophenone at 283.15 K and 288.15 K (below its melting temperature equal 291.76 K) needed for the computation of V m E were determined both from the extrapolation of densities measured at higher temperatures and from excess volume correlation using the respective density value as an adjustable parameter. Both the estimation methods are compared and discussed.
