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Four-Component Reactions for the Synthesis of Perfluoroalkyl Isoxazoles
ACS Catalysis, 2019A four-component strategy for the synthesis of the isoxazole skeleton is developed. The approach achieves the synthesis of perfluoroalkyl isoxazoles by using simple perfluoroalkyl reagents.
Yuanjin Chen +3 more
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Isoxazoles I: Protonation of Isoxazole Derivatives in Aqueous Sulfuric Acid
Journal of Pharmaceutical Sciences, 1973The protonation of 3-amino-5-methylisoxazole, 5-amino-3,4-dimethylisoxazole, sulfamethoxazole (N-sulfanilamido-5-methyl-3-isoxazole), and sulfisoxazole (N-sulfanilamido-3,4-dimethyl-5-isoxazole) in aqueous sulfuric acid was studied. The pKSH+ and log SH+/S or log SH2+2/SH+ values were determined by UV spectrophotometry.
R H, Manzo, M M, De Bertorello
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Journal of Organic Chemistry, 2019
An efficient method for the synthesis of 4-sulfenyl isoxazoles has been developed via AlCl3-mediated electrophilic cyclization/sulfenylation of 2-alkyn-1-one O-methyloximes.
Wenchao Gao +5 more
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An efficient method for the synthesis of 4-sulfenyl isoxazoles has been developed via AlCl3-mediated electrophilic cyclization/sulfenylation of 2-alkyn-1-one O-methyloximes.
Wenchao Gao +5 more
semanticscholar +1 more source
The Journal of Organic Chemistry, 2019
The first synthesis of isoxazole-4-carboxylic acid derivatives by domino isoxazole-isoxazole isomerization is reported. Fe(II)-catalyzed isomerization of 4-acyl-5-methoxy-/5-aminoisoxazoles (dioxane, 105 °C) leads to the formation of isoxazole-4-carboxylic esters and amides in good yields. 4-Formyl-5-methoxyisoxazoles give methyl oxazole-4-carboxylates
Anna V. Serebryannikova +3 more
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The first synthesis of isoxazole-4-carboxylic acid derivatives by domino isoxazole-isoxazole isomerization is reported. Fe(II)-catalyzed isomerization of 4-acyl-5-methoxy-/5-aminoisoxazoles (dioxane, 105 °C) leads to the formation of isoxazole-4-carboxylic esters and amides in good yields. 4-Formyl-5-methoxyisoxazoles give methyl oxazole-4-carboxylates
Anna V. Serebryannikova +3 more
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Trisubstituted isoxazoles from 3,4-disubstituted-(2H)-isoxazol-5-ones
Tetrahedron, 1998Abstract A new trisubstituted isoxazole synthesis, starting from 3,4-disubstituted-(2H)-isoxazol-5-ones, is ...
E.M. Beccalli, M.L. Gelmi, A. Marchesini
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Synthetic Approaches to Nitro-Substituted Isoxazoles
Synthesis, 2019Nitro-substituted isoxazoles are of utmost interest both as versatile intermediates for targeted organic synthesis and as perspective bioactive compounds for drug development.
D. Vasilenko +3 more
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Organic Letters, 2019
The synthesis of isoxazoles has been achieved in a continuous flow system composed of two reaction units: the Friedel-Crafts acylation of alkynes and the azide conjugate addition to the resulting β-chlorovinyl ketones followed by a photochemical-thermal ...
H. Koo, H. Kim, K. Oh
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The synthesis of isoxazoles has been achieved in a continuous flow system composed of two reaction units: the Friedel-Crafts acylation of alkynes and the azide conjugate addition to the resulting β-chlorovinyl ketones followed by a photochemical-thermal ...
H. Koo, H. Kim, K. Oh
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ACS Catalysis, 2019
Cu(II)-catalyzed [4+2]-cycloadditions occur between Cu–benzopyryliums and substituted isoxazoles with the regioselectivity on the C(3,4)-carbons of isoxazoles.
Sovan Sundar Giri, Rai‐Shung Liu
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Cu(II)-catalyzed [4+2]-cycloadditions occur between Cu–benzopyryliums and substituted isoxazoles with the regioselectivity on the C(3,4)-carbons of isoxazoles.
Sovan Sundar Giri, Rai‐Shung Liu
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Organic Letters, 2019
The stereospecific synthesis of Z-enamides is described in this paper. For the first time, isoxazoles have been employed as electrophiles in C-H functionalization to afford thermodynamically less stable Z-enamides utilizing salicylaldehydes in an atom ...
Suvankar Debbarma, S. S. Bera, M. Maji
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The stereospecific synthesis of Z-enamides is described in this paper. For the first time, isoxazoles have been employed as electrophiles in C-H functionalization to afford thermodynamically less stable Z-enamides utilizing salicylaldehydes in an atom ...
Suvankar Debbarma, S. S. Bera, M. Maji
semanticscholar +1 more source
Acta Crystallographica Section C Crystal Structure Communications, 1996
The title compound, ethyl 3-(9-anthryl)-5-methyl-4-isoxazolecarboxylate, C 21 H 17 NO 3 , possesses two planar ring systems that lie at 80° from coplanarity. The bond linking the two ring systems is 1.489 (3) A, indicating only partial conjugation between the two ring systems.
M. D. Mosher, N. R. Natale, A. Vij
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The title compound, ethyl 3-(9-anthryl)-5-methyl-4-isoxazolecarboxylate, C 21 H 17 NO 3 , possesses two planar ring systems that lie at 80° from coplanarity. The bond linking the two ring systems is 1.489 (3) A, indicating only partial conjugation between the two ring systems.
M. D. Mosher, N. R. Natale, A. Vij
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