4,5-(1',4'-Butylene)-3-per(poly) fluoroalkylisoxazoles 2 are synthesized by the reaction of the alpha-per(poly) fluoroalkyl cyclohexanones 1 with hydroxylamine hydrochloride in the presence of potassium carbonate under reflux in ethanol. The isomeric 3,4-(1',4'-butylene)-5-per (poly) fluoroalkylisoxazoles 3 can be prepared by a reaction of 1, first with hydroxylamine hydrochloride to give the corresponding oximes 4, followed by the treatment of the resultant reaction mixture with potassium carbonate in a one-pot procedure.