145616-48-4Relevant articles and documents
Synthesis of 3,6-Dihydro-2 H-1,2-oxazines via Dimethylsulfoxonium Methylide Addition to α,β-Unsaturated Nitrones
Hasegawa, Megumi,Suga, Takuya,Soeta, Takahiro,Ukaji, Yutaka
, p. 11258 - 11264 (2020/10/12)
A unique and efficient formation of 3,6-dihydro-2H-1,2-oxazines starting from α,β-unsaturated nitrones has been achieved. The nucleophilic addition of dimethylsulfoxonium methylide to the C-N bond of an α,β-unsaturated nitrone to form an aziridine N-oxide followed by the Meisenheimer rearrangement affords 3,6-dihydro-2H-1,2-oxazine in up to 70% yield. Methylene was confirmed to be incorporated at the C3 position of the ring. A wide range of β-aryl-substituted α,β-unsaturated nitrones were applicable to this reaction.
A torquoselective extrusion of isoxazoline N-oxides. Application to the synthesis of aryl vinyl and divinyl ketones for Nazarov cyclization
Canterbury, Daniel P.,Herrick, Ildiko R.,Um, Joann,Houk,Frontier, Alison J.
experimental part, p. 3165 - 3179 (2009/09/05)
A mild, convenient reaction sequence for the synthesis of Nazarov cyclization substrates is described. The [3+2] dipolar cycloaddition of a nitrone and an electron-deficient alkyne gives an isolable isoxazoline intermediate, which upon oxidation undergoes stereoselective extrusion of nitrosomethane to give aryl vinyl or divinyl ketones.
Ring-opening of isoxazolidine system: Homologation of 3-aryl into 3-styryl nitrones via intermediate 5-hydroxy-isoxazolidines
Chiacchio, Ugo,Liguori, Angelo,Romeo, Giovanni,Sindona, Giovanni,Uccella, Nicola
, p. 9473 - 9482 (2007/10/02)
High yield conversion of 3-aryl-5-ethoxy-isoxazolidines into 3-styryl nitrones has been achieved by 1,5 h refluxing in aq. H2SO4 or catalytic p-toluensulfonic acid/ethanol media. The rearrangement pathway is interpretable on the basis of the ring-opening process of intermediate 5-hydroxy-isoxazolidines. Formation of a masked 5-OH function has been also developed by basic or acid treatment of 5-acetoxy-isoxazolidines.
