The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Marino Petrini - One of the best experts on this subject based on the ideXlab platform.
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synthesis of functionalized nitroalkanes by oxidation of oximes with urea hydrogen peroxide complex and Trifluoroacetic Anhydride
Tetrahedron Letters, 1992Co-Authors: Roberto Ballini, Enrico Marcantoni, Marino PetriniAbstract:Abstract Reaction of urea-hydrogen peroxide complex with Trifluoroacetic Anhydride in acetonitrile at 0°C affords in a safe and easy fashion anhydrous solutions of peroxyTrifluoroacetic acid. These can be used to oxidize aldoximes to nitroalkanes in good yields. Ketoximes fail to react in these conditions and are cleaved to the parent carbonyl compounds.
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Synthesis of Functionalized Nitroalkanes by Oxidation of Oximes with Urea-Hydrogen Peroxide Complex and Trifluoroacetic Anhydride.”
Tetrahedron Letters, 1992Co-Authors: Roberto Ballini, Enrico Marcantoni, Marino PetriniAbstract:Abstract Reaction of urea-hydrogen peroxide complex with Trifluoroacetic Anhydride in acetonitrile at 0°C affords in a safe and easy fashion anhydrous solutions of peroxyTrifluoroacetic acid. These can be used to oxidize aldoximes to nitroalkanes in good yields. Ketoximes fail to react in these conditions and are cleaved to the parent carbonyl compounds.
Masami Kawase - One of the best experts on this subject based on the ideXlab platform.
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The Dakin-West Reaction of N-Alkoxycarbonyl-N-alkyl-α-amino Acids Employing Trifluoroacetic Anhydride
Chemical & pharmaceutical bulletin, 2000Co-Authors: Masami Kawase, Michitaka Hirabayashi, Hiroko Kumakura, Setsuo Saito, Katsumi YamamotoAbstract:The Dakin-West reaction of N-alkoxycarbonyl-N-alkyl-alpha-amino acids (1a-j) with Trifluoroacetic Anhydride in the presence of pyridine gave alpha-amido trifluoromethyl ketones (2a-j), in which probable intermediates were mesoionic 1,3-oxazolium-5-olates (munchnones). The diastereoselective reduction of 2a-f with NaBH4 gave the threo-aminoalcohols (5a-f), which may be explained by the Felkin-Anh model. This was confirmed by converting 5a-f into trans-5-trifluoromethyl-2-oxazolidinones (6a-f) in good yields.
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An anomalous Dakin–West reaction of N-carbamate substituted prolines and Trifluoroacetic Anhydride
Chemical Communications, 1998Co-Authors: Masami Kawase, Michitaka Hirabayashi, Hiromi Koiwai, Katsumi Yamamoto, Hiroshi MiyamaeAbstract:A novel transformation of N-alkoxycarbonylprolines 1 to 4-trifluoroacetyl-2,3-dihydropyrroles 2 was efficiently realized by utilizing Trifluoroacetic Anhydride, in which probable intermediates were mesoionic 1,3-oxazolium-5-olates B.
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an anomalous dakin west reaction of n carbamate substituted prolines and Trifluoroacetic Anhydride
Chemical Communications, 1998Co-Authors: Masami Kawase, Michitaka Hirabayashi, Hiromi Koiwai, Katsumi Yamamoto, Hiroshi MiyamaeAbstract:A novel transformation of N-alkoxycarbonylprolines 1 to 4-trifluoroacetyl-2,3-dihydropyrroles 2 was efficiently realized by utilizing Trifluoroacetic Anhydride, in which probable intermediates were mesoionic 1,3-oxazolium-5-olates B.
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Unusual reactions of Secondary amino acids with Trifluoroacetic Anhydride : a novel access to α-trifluoromethylated acyloins
Tetrahedron Letters, 1994Co-Authors: Masami KawaseAbstract:A new fragmentation reaction of secondary α-amino acids with Trifluoroacetic Anhydride under Dakin-West reaction conditions proceeds through oxazolium salt intermediates followed by ring cleavage to form α-trifluoromethylated acyloins in good yields.
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Unexpected product from the Dakin-West reaction of N-acylprolines using Trifluoroacetic Anhydride: A novel access to 5-trifluoromethyloxazoles
Tetrahedron Letters, 1993Co-Authors: Masami Kawase, Hiroshi Miyamae, Mariko Narita, Teruo KuriharaAbstract:Abstract The base-catalyzed reaction of N-acylprolines with Trifluoroacetic Anhydride proceeds through mesoionic 1,3-oxazolium-5-olates followed by the pyrrolidine ring cleavage to afford the 5-trifluoromethyloxazoles in good yields.
Roberto Ballini - One of the best experts on this subject based on the ideXlab platform.
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synthesis of functionalized nitroalkanes by oxidation of oximes with urea hydrogen peroxide complex and Trifluoroacetic Anhydride
Tetrahedron Letters, 1992Co-Authors: Roberto Ballini, Enrico Marcantoni, Marino PetriniAbstract:Abstract Reaction of urea-hydrogen peroxide complex with Trifluoroacetic Anhydride in acetonitrile at 0°C affords in a safe and easy fashion anhydrous solutions of peroxyTrifluoroacetic acid. These can be used to oxidize aldoximes to nitroalkanes in good yields. Ketoximes fail to react in these conditions and are cleaved to the parent carbonyl compounds.
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Synthesis of Functionalized Nitroalkanes by Oxidation of Oximes with Urea-Hydrogen Peroxide Complex and Trifluoroacetic Anhydride.”
Tetrahedron Letters, 1992Co-Authors: Roberto Ballini, Enrico Marcantoni, Marino PetriniAbstract:Abstract Reaction of urea-hydrogen peroxide complex with Trifluoroacetic Anhydride in acetonitrile at 0°C affords in a safe and easy fashion anhydrous solutions of peroxyTrifluoroacetic acid. These can be used to oxidize aldoximes to nitroalkanes in good yields. Ketoximes fail to react in these conditions and are cleaved to the parent carbonyl compounds.
Yashwant D. Vankar - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of 2-Nitroglycals from Glycals Using the Tetrabutylammonium Nitrate–Trifluoroacetic Anhydride–Triethylamine Reagent System and Base-Catalyzed Ferrier Rearrangement of Acetylated 2-Nitroglycals
The Journal of organic chemistry, 2013Co-Authors: Suresh Dharuman, Preeti Gupta, Pavan K. Kancharla, Yashwant D. VankarAbstract:A reagent system comprising tetrabutylammonium nitrate–Trifluoroacetic Anhydride–triethylamine has been developed for the synthesis of 2-nitroglycals from various protected glycals. The base-catalyzed Ferrier rearrangement on tri-O-acetylated 2-nitroglycals has been reported for the first time. Reactivity of these nitroacetates and associated selectivity has been examined, and some of the products have been converted into 2,3-diamino-2,3-dideoxyglycosides and methyl N-acetyl-d-lividosaminide.
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synthesis of 2 nitroglycals from glycals using the tetrabutylammonium nitrate Trifluoroacetic Anhydride triethylamine reagent system and base catalyzed ferrier rearrangement of acetylated 2 nitroglycals
Journal of Organic Chemistry, 2013Co-Authors: Suresh Dharuman, Preeti Gupta, Pavan K. Kancharla, Yashwant D. VankarAbstract:A reagent system comprising tetrabutylammonium nitrate–Trifluoroacetic Anhydride–triethylamine has been developed for the synthesis of 2-nitroglycals from various protected glycals. The base-catalyzed Ferrier rearrangement on tri-O-acetylated 2-nitroglycals has been reported for the first time. Reactivity of these nitroacetates and associated selectivity has been examined, and some of the products have been converted into 2,3-diamino-2,3-dideoxyglycosides and methyl N-acetyl-d-lividosaminide.
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Synthesis of 2‑Nitroglycals from Glycals Using the Tetrabutylammonium Nitrate–Trifluoroacetic Anhydride–Triethylamine Reagent System and Base-Catalyzed Ferrier Rearrangement of Acetylated 2‑Nitroglycals
2013Co-Authors: Suresh Dharuman, Preeti Gupta, Pavan K. Kancharla, Yashwant D. VankarAbstract:A reagent system comprising tetrabutylammonium nitrate–Trifluoroacetic Anhydride–triethylamine has been developed for the synthesis of 2-nitroglycals from various protected glycals. The base-catalyzed Ferrier rearrangement on tri-O-acetylated 2-nitroglycals has been reported for the first time. Reactivity of these nitroacetates and associated selectivity has been examined, and some of the products have been converted into 2,3-diamino-2,3-dideoxyglycosides and methyl N-acetyl-d-lividosaminide
Zbigniew H. Kudzin - One of the best experts on this subject based on the ideXlab platform.
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Trifluoroacetic Anhydride-sodium iodide reagent. Nature and applications
Arkivoc, 2007Co-Authors: Zbigniew H. Kudzin, Józef Drabowicz, Marcin H. Kudzin, Andrzej KotyńskiAbstract:Trifluoroacetic Anhydride - sodium iodide mixture (TFAA-NaI; TFAA-I) reacts with several compounds bearing semipolar X-O bond, usually in the mode of deoxygenation, with liberation of iodine. The results of systematic investigations of the TFAA-I-reaction with various types of S-oxo and N-oxo compounds were discussed. The majority of these reactions are characterized by quantitative course, with respect to both X-O substrate transformation as well as to the amounts of liberated iodine. On this basis, a variety of sulphoxides and sulphimides were successfully reduced to sulphides and/or arene-N-oxides to amines, using TFAA-I at ambient temperature. Arene- and alkyl-sulphonic acids were reduced to the corresponding thiol derivatives in moderate yields. Stoichiometric course of the TFAA-I reaction with several S-oxo and N-oxo compounds gave origin to their analytical determinations. Thus, due to stoichiometric amounts of iodine formed from sulphoxides, sulphimides, arene-N-oxides, nitrones and nitroxide radicals, and nitroso compounds - the TFAA-I reagent can be applied to their analytical determination (titrimetric on µmol and spectrometric on nmol scale) and/or TLC detection.
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The Trifluoroacetic Anhydride-sodium iodide system as a reagent for determination and microdetermination of nitroxide radicals.
Talanta, 1995Co-Authors: Witold Ciesielski, Zbigniew H. Kudzin, Grzegorz GrabowskiAbstract:Abstract A Trifluoroacetic Anhydride-sodium iodide mixture (TFAA-I) reacts with nitroxide radicals with liberation of iodine. Since stoichiometric amounts of iodine are formed from nitroxides, the TFAA-I reagent can be applied to their analytical determination. Two procedures for the determination of nitroxides (titrimetric on μmol and spectrometric on nmol levels) are described.
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Application of Trifluoroacetic Anhydride-sodium iodide reagent for selective detection in thin-layer chromatography: IV. Thin-layer chromatographic differentiation of nitrones, nitroxide radicals and nitrosoamines in mixtures
Journal of Chromatography A, 1994Co-Authors: Andrzej Kotyński, Zbigniew H. KudzinAbstract:Trifluoroacetic Anhydride-sodium iodide mixture (TFAA-I) reacts with nitroxide radicals, nitrones and nitrosoamines with release of iodine. Methods for the differentiation of these groups of nitrogen derivatives containing the N-O moiety using TLC systems with TFAA-I detection reagent are described.