A new synthesis of 2-isoxazoline2-oxides starting from unsaturated nitro compounds is described. A facile and convenient preparation of β-alkyl substituted β-nitroenones and their conversion to β-nitrosulfides are recorded. Treatment of these compounds with potassium tert-butoxide at −78°C followed by immediate quenching with acetic acid provides access to 5-hydroxy-4-(phenylthio)-2-isoxazoline 2-oxides