The Experts below are selected from a list of 108 Experts worldwide ranked by ideXlab platform
Roderic P. Quirk - One of the best experts on this subject based on the ideXlab platform.
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Anionic synthesis of aromatic amide and carboxyl functionalized polymers. Chain-end functionalization of poly(styryl)lithium withN,N-diisopropyl-4-(1-phenylethenyl)benzamide
Journal of Polymer Science Part A: Polymer Chemistry, 1998Co-Authors: Gabriel J. Summers, Roderic P. QuirkAbstract:The novel syntheses of N,N-diisopropyl-4-benzoylbenzamide, N,N-diisopropyl-4-(1-hydroxy-1-phenylethyl)benzamide, and N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1) are described. ω-Amidopolystyrene (2) was synthesized in quantitative yields by the reaction of poly(styryl)lithium with stoichiometric amounts of N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1) in toluene/tetrahydrofuran (4 : 1 v/v) at −78°C. Deblocking of the amide protecting group by acid hydrolysis quantitatively provides the corresponding aromatic carboxyl chain-end functionalized polystyrene (3). The functionalization agent and functionalized polymers were characterized by HPLC, thin-layer chromatography, size exclusion chromatography, Vapor Phase Osmometry, spectroscopy (1H-NMR, 13C-NMR, and FTIR), potentiometry, and elemental analysis. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1233–1241, 1998
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Anionic synthesis of aromatic carboxyl functionalized polymers. Chain-end functionalization of poly(styryl)lithium with 4,5-dihydro-4,4-dimethyl-2-[4-(1-phenylethenyl)phenyl] oxazole
Polymer International, 1996Co-Authors: Gabriel J. Summers, Roderic P. QuirkAbstract:The novel syntheses of 4-(4,5-dihydro-4,4-dimethyl-2- oxazolyl)benzophenone, 1-[4-(4,5-dihydro-4,4-dimethyl-2-oxazolyl)phenyl]-1-phenylethanol and 4,5-dihydro-4,4-dimethyl-2-[4-(1-phenylethenyl)phenyl]oxazole (1) are described. ω-Oxazolyl polystyrene (2) was synthesized in quantitative yields by the reaction of poly(styryl)lithium with stoichiometric amounts of 4,5-dihydro-4,4-dimethyl-2-[4-(1-phenylethenyl)phenyl]oxazole (1) in toluene/tetrahydrofuran (4 :1 v/v) at -78°C. Deblocking of the oxazoline protecting group by acid hydrolysis followed by saponification quantitatively provides the corresponding aromatic carboxyl chain-end functionalized polystyrene (3). The functionalization agent and functionalized polymers were characterized by HPLC, thin layer chromatography, size exclusion chromatography, Vapor Phase Osmometry, spectroscopy ( 1 H NMR, 13 C NMR and FTIR), potentiometry and elemental analysis.
Gabriel J. Summers - One of the best experts on this subject based on the ideXlab platform.
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Anionic synthesis of aromatic amide and carboxyl functionalized polymers. Chain-end functionalization of poly(styryl)lithium withN,N-diisopropyl-4-(1-phenylethenyl)benzamide
Journal of Polymer Science Part A: Polymer Chemistry, 1998Co-Authors: Gabriel J. Summers, Roderic P. QuirkAbstract:The novel syntheses of N,N-diisopropyl-4-benzoylbenzamide, N,N-diisopropyl-4-(1-hydroxy-1-phenylethyl)benzamide, and N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1) are described. ω-Amidopolystyrene (2) was synthesized in quantitative yields by the reaction of poly(styryl)lithium with stoichiometric amounts of N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1) in toluene/tetrahydrofuran (4 : 1 v/v) at −78°C. Deblocking of the amide protecting group by acid hydrolysis quantitatively provides the corresponding aromatic carboxyl chain-end functionalized polystyrene (3). The functionalization agent and functionalized polymers were characterized by HPLC, thin-layer chromatography, size exclusion chromatography, Vapor Phase Osmometry, spectroscopy (1H-NMR, 13C-NMR, and FTIR), potentiometry, and elemental analysis. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1233–1241, 1998
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Anionic synthesis of aromatic carboxyl functionalized polymers. Chain-end functionalization of poly(styryl)lithium with 4,5-dihydro-4,4-dimethyl-2-[4-(1-phenylethenyl)phenyl] oxazole
Polymer International, 1996Co-Authors: Gabriel J. Summers, Roderic P. QuirkAbstract:The novel syntheses of 4-(4,5-dihydro-4,4-dimethyl-2- oxazolyl)benzophenone, 1-[4-(4,5-dihydro-4,4-dimethyl-2-oxazolyl)phenyl]-1-phenylethanol and 4,5-dihydro-4,4-dimethyl-2-[4-(1-phenylethenyl)phenyl]oxazole (1) are described. ω-Oxazolyl polystyrene (2) was synthesized in quantitative yields by the reaction of poly(styryl)lithium with stoichiometric amounts of 4,5-dihydro-4,4-dimethyl-2-[4-(1-phenylethenyl)phenyl]oxazole (1) in toluene/tetrahydrofuran (4 :1 v/v) at -78°C. Deblocking of the oxazoline protecting group by acid hydrolysis followed by saponification quantitatively provides the corresponding aromatic carboxyl chain-end functionalized polystyrene (3). The functionalization agent and functionalized polymers were characterized by HPLC, thin layer chromatography, size exclusion chromatography, Vapor Phase Osmometry, spectroscopy ( 1 H NMR, 13 C NMR and FTIR), potentiometry and elemental analysis.
Murali Ramanathan - One of the best experts on this subject based on the ideXlab platform.
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Rapid Solubility Determination Using Vapor-Phase Osmometry.
Journal of biomolecular screening, 1999Co-Authors: Hemanshu H. Parikh, Vandana Balasubramanian, Wai L. Chul, Marilyn E. Morris, Murali RamanathanAbstract:Because of the need for resource-sparing assays of the solubility of new drug candidates, we sought to develop and validate a rapid method for determining the solubility of nonvolatile pharmaceutical solids in water. Vapor-Phase Osmometry was used to determine the concentration of drugs in saturated solutions prepared by a rapid ultrasound-mediated dissolution protocol. The osmolality of saturated solutions as measured by the Vapor-Phase osmometer is an excellent predictor of the solubility of pharmaceutical solids in water. Each osmolality measurement requires less than 10 ul of saturated solution and takes less than 2 min to complete. For small-molecule drugs with solubilities greater than 10 g/kg, Osmometry may prove to be a rapid and accurate method for determining the water solubilities of drugs.
Hemanshu H. Parikh - One of the best experts on this subject based on the ideXlab platform.
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Rapid Solubility Determination Using Vapor-Phase Osmometry.
Journal of biomolecular screening, 1999Co-Authors: Hemanshu H. Parikh, Vandana Balasubramanian, Wai L. Chul, Marilyn E. Morris, Murali RamanathanAbstract:Because of the need for resource-sparing assays of the solubility of new drug candidates, we sought to develop and validate a rapid method for determining the solubility of nonvolatile pharmaceutical solids in water. Vapor-Phase Osmometry was used to determine the concentration of drugs in saturated solutions prepared by a rapid ultrasound-mediated dissolution protocol. The osmolality of saturated solutions as measured by the Vapor-Phase osmometer is an excellent predictor of the solubility of pharmaceutical solids in water. Each osmolality measurement requires less than 10 ul of saturated solution and takes less than 2 min to complete. For small-molecule drugs with solubilities greater than 10 g/kg, Osmometry may prove to be a rapid and accurate method for determining the water solubilities of drugs.
Gary L Turner - One of the best experts on this subject based on the ideXlab platform.
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anion distributions in sodium silicate solutions characterization by 29si nmr and infrared spectroscopies and Vapor Phase Osmometry
Journal of Physical Chemistry B, 1997Co-Authors: Jonathan L Bass, Gary L TurnerAbstract:Soluble silicates are complex mixtures of silicate anions. The larger anions are two- or three-dimensional condensation products of silicate monomer, SiO4-4. In more siliceous silicate solutions, i.e., SiO2:Na2O ratio >2.0, some of the silicate condenses to polymeric (colloidal) silica. Negative charges on the anions are balanced by protons or by cations, typically alkali metal or quaternary alkylammonium cations. The distribution of these anions varies with the concentration of dissolved silicate solids, the relative molar concentrations of cations and silica, and to a lesser extent, trace impurities. 29Silicon NMR spectroscopy of silicate solutions has been a powerful method for studying the connectivity of silicon and oxygen atoms in silicate solutions. In this paper we will show how variations in silicate band shape and peak location in the mid-infrared spectrum from 700 to 1300 cm-1 depend on concentration and silica:alkali ratio. We will interpret the infrared data in consonance with NMR results. We...
