Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Synthesis of Isoxazole- And Oxazole-4-carboxylic Acids Derivatives by Controlled Isoxazole-Azirine-Isoxazole/Oxazole Isomerization. / Serebryannikova, Anna V.; Galenko, Ekaterina E.; Novikov, Mikhail S.; Khlebnikov, Alexander F.
в: Journal of Organic Chemistry, Том 84, № 23, 06.12.2019, стр. 15567-15577.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Synthesis of Isoxazole- And Oxazole-4-carboxylic Acids Derivatives by Controlled Isoxazole-Azirine-Isoxazole/Oxazole Isomerization
AU - Serebryannikova, Anna V.
AU - Galenko, Ekaterina E.
AU - Novikov, Mikhail S.
AU - Khlebnikov, Alexander F.
N1 - Publisher Copyright: Copyright © 2019 American Chemical Society.
PY - 2019/12/6
Y1 - 2019/12/6
N2 - 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 under the same reaction conditions. Fe(II)-catalyzed isomerization of 4-acyl-5-methoxyisoxazoles under milder conditions (MeCN, 50 °C) allows the preparation of transient 2-acyl-2-(methoxycarbonyl)-2H-azirines. The azirines isomerize quantitatively either into isoxazoles under catalytic conditions (dioxane, 105 °C) or into oxazoles under noncatalytic thermolysis (o-dichlorobenzene, 170 °C). The mechanism of the isomerization and dependence of the reaction routes on substituents at starting isoxazole core and reaction conditions are discussed on the basis of DFT calculations.
AB - 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 under the same reaction conditions. Fe(II)-catalyzed isomerization of 4-acyl-5-methoxyisoxazoles under milder conditions (MeCN, 50 °C) allows the preparation of transient 2-acyl-2-(methoxycarbonyl)-2H-azirines. The azirines isomerize quantitatively either into isoxazoles under catalytic conditions (dioxane, 105 °C) or into oxazoles under noncatalytic thermolysis (o-dichlorobenzene, 170 °C). The mechanism of the isomerization and dependence of the reaction routes on substituents at starting isoxazole core and reaction conditions are discussed on the basis of DFT calculations.
KW - NITRILE OXIDES
KW - RING
KW - REACTIVITY
KW - CHLORIDES
KW - OXAZOLES
KW - PHOTOCHEMISTRY
KW - CYCLOADDITION
KW - CYCLIZATION
KW - 2H-AZIRINES
UR - http://www.scopus.com/inward/record.url?scp=85074763606&partnerID=8YFLogxK
UR - http://www.mendeley.com/research/synthesis-isoxazole-oxazole4carboxylic-acids-derivatives-controlled-isoxazoleazirineisoxazoleoxazole
U2 - 10.1021/acs.joc.9b02536
DO - 10.1021/acs.joc.9b02536
M3 - Article
C2 - 31658810
AN - SCOPUS:85074763606
VL - 84
SP - 15567
EP - 15577
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
SN - 0022-3263
IS - 23
ER -
ID: 49487604