New versatile syntheses of 3-aminoisoxazoles and their derivatives are described. 3-(N, N-Disubstituted amino) isoxazoles 5 were synthesized by heating 3-chloro-2-methylisoxazolium chlorides 1 with secondary amines, or by the substitution reaction of 1 with primary amines, followed by the dehydrochlorination and the subsequent addition-elimination reaction of alkyl or acyl halides with the resulting imines 6. Among the products 5, 3-(N-substituted acetylamino) isoxazoles were hydrolyzed with base to give 3-(N-monosubstituted amino) isoxazoles 3. 3-Aminoisoxazoles 7 were synthesized by the reaction of 1 with potassium phthalimide, followed by treatment with hydrazine.
One-Pot Three-Component Heteroannulation of β-Oxo Dithioesters, Amines and Hydroxylamine: Regioselective, Facile and Straightforward Entry to 5-Substituted 3-Aminoisoxazoles
amine, which undergoes nucleophilic attack by hydroxylamine followed by intramolecular cyclization with the oxo functionality and subsequent dehydration to give 5-substituted 3-aminoisoxazoles as a single regioisomer in good yields. Furthermore, the mechanism of the reaction has been established experimentally and shown to be in agreement with the hard and soft (Lewis) acid and base (HSAB) theory.
Boberg,F.; von Gentzkow,W., Justus Liebigs Annalen der Chemie, 1973, p. 256 - 262
作者:Boberg,F.、von Gentzkow,W.
DOI:——
日期:——
Reaction of α-Ketoketene<i>S,N</i>-Acetals with Hydroxylamine: A Facile General Route to 5-Aryl-3-(<i>N</i>-arylamino,<i>N</i>-alkylamino, or<i>N</i>-azacycloalkyl)-isoxazoles
作者:A. Rahman、J. N. Vishwakarma、R. D. Yadav、H. Ila、H. Junjappa
DOI:10.1055/s-1984-30793
日期:——
Certain Halogen and Nitro Derivatives of 3-Anilino-5-phenylisoxazole and Pyrazole