130628-67-0Relevant articles and documents
Synthese d'isoxazoles substitues en α de l'azote par une chaine alkyle ou alcenyle
Cherton, Jean-Claude,Lanson, Marc,Ladjama, Daif,Guichon, Yvette,Basselier, Jean-Jacques
, p. 1271 - 1276 (2007/10/02)
Several syntheses of special isoxazoles bearing a long alkyl or alkenyl side chain in the α position of the nitrogen are presented.A very convenient route in the case of an alkyl side chain is the classical 1,3-dipolar cycloaddition of a nitrile-oxide to a vinyl acetate.Although it is a rather long approach, the reaction of hydroxylamine with enone-epoxides represents a new and unequivocal method compatible with alkenyl side chains.The isomerisation of the easily synthesized isoxazoles bearing such substituents α to the oxygen, by the reaction of their isoxazolium salts with hydroxylamine, is a fast and general method.Another very convenient access to "α-N substituted" isoxazoles is the coupling of magnesium compounds with 3-bromomethyl 5-methyl isoxazole.