The Experts below are selected from a list of 6894 Experts worldwide ranked by ideXlab platform
Matthias Brewer - One of the best experts on this subject based on the ideXlab platform.
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iodine iii mediated bicyclic diazenium Salt Formation
ChemInform, 2013Co-Authors: Nezar Q Albataineh, Matthias BrewerAbstract:Treatment of arylhydrazones (I) with Ph-I(O-Tf)2, generated in situ, results in Formation of bicyclic diazenium Salts.
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iodine iii mediated bicyclic diazenium Salt Formation
Tetrahedron Letters, 2012Co-Authors: Nezar Q Albataineh, Matthias BrewerAbstract:Abstract The hypervalent iodine(III) reagent PhI(OTf) 2 has been shown to be an effective oxidant for the conversion of linear aryl-hydrazones bearing a pendant alkene into bicyclic diazenium Salts. This oxidative cyclization presumably occurs by the iodine(III) mediated Formation of a 1-aza-2-azoniaallene Salt intermediate that undergoes a subsequent intramolecular 1,3-dipolar cycloaddition with the pendant alkene.
Nezar Q Albataineh - One of the best experts on this subject based on the ideXlab platform.
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iodine iii mediated bicyclic diazenium Salt Formation
ChemInform, 2013Co-Authors: Nezar Q Albataineh, Matthias BrewerAbstract:Treatment of arylhydrazones (I) with Ph-I(O-Tf)2, generated in situ, results in Formation of bicyclic diazenium Salts.
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iodine iii mediated bicyclic diazenium Salt Formation
Tetrahedron Letters, 2012Co-Authors: Nezar Q Albataineh, Matthias BrewerAbstract:Abstract The hypervalent iodine(III) reagent PhI(OTf) 2 has been shown to be an effective oxidant for the conversion of linear aryl-hydrazones bearing a pendant alkene into bicyclic diazenium Salts. This oxidative cyclization presumably occurs by the iodine(III) mediated Formation of a 1-aza-2-azoniaallene Salt intermediate that undergoes a subsequent intramolecular 1,3-dipolar cycloaddition with the pendant alkene.
Michael H Weber - One of the best experts on this subject based on the ideXlab platform.
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pedagogical comparison of five reactions performed under microwave heating in multi mode versus mono mode ovens diels alder cycloaddition wittig Salt Formation e2 dehydrohalogenation to form an alkyne williamson ether synthesis and fischer esterifica
Journal of Chemical Education, 2014Co-Authors: Marsha R Baar, William Gammerdinger, Jennifer Leap, Erin Morales, Jonathan Shikora, Michael H WeberAbstract:Five reactions were rate-accelerated relative to the standard reflux workup in both multi-mode and mono-mode microwave ovens, and the results were compared to determine whether the sequential processing of a mono-mode unit could provide for better lab logistics and pedagogy. Conditions were optimized so that yields matched in both types of microwave ovens for a Diels–Alder cycloaddition, Wittig Salt Formation, Fischer esterifications, an E2 alkyne Formation, and Williamson ether synthesis. Typically, a 10-fold rate acceleration was observed under mono-mode heating versus multi-mode heating, reducing the total run-time between 1.5 and 3.0 min per sample, which rivals the batch run-time of a multi-mode unit in ∼16 student lab sections. Thus, the mono-mode microwave oven required a similar quantity of total reaction time in the lab, allowing students to run their experiments individually with less wait-time, competition for chemicals, equipment, and instrumentation and to complete the experiments in the lab ...
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Pedagogical Comparison of Five Reactions Performed under Microwave Heating in Multi-Mode versus Mono-Mode Ovens: Diels–Alder Cycloaddition, Wittig Salt Formation, E2 Dehydrohalogenation To Form an Alkyne, Williamson Ether Synthesis, and Fischer Ester
Journal of Chemical Education, 2014Co-Authors: Marsha R Baar, William Gammerdinger, Jennifer Leap, Erin Morales, Jonathan Shikora, Michael H WeberAbstract:Five reactions were rate-accelerated relative to the standard reflux workup in both multi-mode and mono-mode microwave ovens, and the results were compared to determine whether the sequential processing of a mono-mode unit could provide for better lab logistics and pedagogy. Conditions were optimized so that yields matched in both types of microwave ovens for a Diels–Alder cycloaddition, Wittig Salt Formation, Fischer esterifications, an E2 alkyne Formation, and Williamson ether synthesis. Typically, a 10-fold rate acceleration was observed under mono-mode heating versus multi-mode heating, reducing the total run-time between 1.5 and 3.0 min per sample, which rivals the batch run-time of a multi-mode unit in ∼16 student lab sections. Thus, the mono-mode microwave oven required a similar quantity of total reaction time in the lab, allowing students to run their experiments individually with less wait-time, competition for chemicals, equipment, and instrumentation and to complete the experiments in the lab ...
Abu T M Serajuddin - One of the best experts on this subject based on the ideXlab platform.
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Salt Formation to improve drug solubility
Advanced Drug Delivery Reviews, 2007Co-Authors: Abu T M SerajuddinAbstract:Salt Formation is the most common and effective method of increasing solubility and dissolution rates of acidic and basic drugs. In this article, physicochemical principles of Salt solubility are presented, with special reference to the influence of pH–solubility profiles of acidic and basic drugs on Salt Formation and dissolution. Non-ideality of Salt solubility due to self-association in solution is also discussed. Whether certain acidic or basic drugs would form Salts and, if Salts are formed, how easily they would dissociate back into their free acid or base forms depend on interrelationships of several factors, such as S0 (intrinsic solubility), pH, pKa, Ksp (solubility product) and pHmax (pH of maximum solubility). The interrelationships of these factors are elaborated and their influence on Salt screening and the selection of optimal Salt forms for development are discussed. Factors influencing Salt dissolution under various pH conditions, and especially in reactive media and in presence of excess common ions, are discussed, with practical reference to the development of solid dosage forms.
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Salt Formation to improve drug solubility
Advanced Drug Delivery Reviews, 2007Co-Authors: Abu T M SerajuddinAbstract:Salt Formation is the most common and effective method of increasing solubility and dissolution rates of acidic and basic drugs. In this article, physicochemical principles of Salt solubility are presented, with special reference to the influence of pH-solubility profiles of acidic and basic drugs on Salt Formation and dissolution. Non-ideality of Salt solubility due to self-association in solution is also discussed. Whether certain acidic or basic drugs would form Salts and, if Salts are formed, how easily they would dissociate back into their free acid or base forms depend on interrelationships of several factors, such as S0 (intrinsic solubility), pH, pKa, Ksp (solubility product) and pHmax (pH of maximum solubility). The interrelationships of these factors are elaborated and their influence on Salt screening and the selection of optimal Salt forms for development are discussed. Factors influencing Salt dissolution under various pH conditions, and especially in reactive media and in presence of excess common ions, are discussed, with practical reference to the development of solid dosage forms. ?? 2007 Elsevier B.V. All rights reserved.
Marsha R Baar - One of the best experts on this subject based on the ideXlab platform.
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pedagogical comparison of five reactions performed under microwave heating in multi mode versus mono mode ovens diels alder cycloaddition wittig Salt Formation e2 dehydrohalogenation to form an alkyne williamson ether synthesis and fischer esterifica
Journal of Chemical Education, 2014Co-Authors: Marsha R Baar, William Gammerdinger, Jennifer Leap, Erin Morales, Jonathan Shikora, Michael H WeberAbstract:Five reactions were rate-accelerated relative to the standard reflux workup in both multi-mode and mono-mode microwave ovens, and the results were compared to determine whether the sequential processing of a mono-mode unit could provide for better lab logistics and pedagogy. Conditions were optimized so that yields matched in both types of microwave ovens for a Diels–Alder cycloaddition, Wittig Salt Formation, Fischer esterifications, an E2 alkyne Formation, and Williamson ether synthesis. Typically, a 10-fold rate acceleration was observed under mono-mode heating versus multi-mode heating, reducing the total run-time between 1.5 and 3.0 min per sample, which rivals the batch run-time of a multi-mode unit in ∼16 student lab sections. Thus, the mono-mode microwave oven required a similar quantity of total reaction time in the lab, allowing students to run their experiments individually with less wait-time, competition for chemicals, equipment, and instrumentation and to complete the experiments in the lab ...
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Pedagogical Comparison of Five Reactions Performed under Microwave Heating in Multi-Mode versus Mono-Mode Ovens: Diels–Alder Cycloaddition, Wittig Salt Formation, E2 Dehydrohalogenation To Form an Alkyne, Williamson Ether Synthesis, and Fischer Ester
Journal of Chemical Education, 2014Co-Authors: Marsha R Baar, William Gammerdinger, Jennifer Leap, Erin Morales, Jonathan Shikora, Michael H WeberAbstract:Five reactions were rate-accelerated relative to the standard reflux workup in both multi-mode and mono-mode microwave ovens, and the results were compared to determine whether the sequential processing of a mono-mode unit could provide for better lab logistics and pedagogy. Conditions were optimized so that yields matched in both types of microwave ovens for a Diels–Alder cycloaddition, Wittig Salt Formation, Fischer esterifications, an E2 alkyne Formation, and Williamson ether synthesis. Typically, a 10-fold rate acceleration was observed under mono-mode heating versus multi-mode heating, reducing the total run-time between 1.5 and 3.0 min per sample, which rivals the batch run-time of a multi-mode unit in ∼16 student lab sections. Thus, the mono-mode microwave oven required a similar quantity of total reaction time in the lab, allowing students to run their experiments individually with less wait-time, competition for chemicals, equipment, and instrumentation and to complete the experiments in the lab ...
