The reaction of hydroxylamine with aryl trifluoromethyl-β-diketones: Synthesis of 5-hydroxy-5-trifluoromethyl-Δ~2-isoxazolines and their dehydration to 5-trifluoromethylisoxazoles

摘要

Reaction of hydroxylamine hydrochloride with aryl trifluoromethyl-β-diketones affords 5-hydroxy-5-trifluoromethyl-Δ~2-isoxazolines rather than the reported 3-trifluoromethylisoxazoles.The structural assignment is based on the analysis of their NMR(~1H,~(13)C and ~(19)F)spectral data and of their dehydration products,5-trifluoromethylisoxazoles.