Reactions of 3,3-dialkyl-2,3-dihydro-6-trifluoromethyl-4-pyrones with hydroxylamine. Synthesis and structures of 5-(1,1-dialkyl-2-hydroxyethyl)-5-hydroxy-3-trifluoromethyl-Δ2-isoxazolines

Abstract

b,4. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 ul. Vavilova, I17o~ Moscow, The reactions of 3,3-dialkyl-2,3-dihydro-6-trifluoronmthyl-4-pyrones with hydroxylamine hydrochloridc afforded regioisomeric 3(5)-(1,1 -dialkyl-2-hydroxyed~yl)-5-hydroxy-5(3)-trifluoromethyt-A2-isoxazotines depending on the re,~ction conditions. The titie compounds were also prepared from 2, 2-dialkyl-5-anuno-l-hydroxy-6,6,6-trifluorohcx-4-en-3-ones. The above dihydropyrones reacted with hydroxylamine (base) to yield 3-(,1, l-dialkyl-2-hydroxyet hyl)-5-hyd roxyamino-5-t ri fhJoromet hyI-A2-isoxazolines.