The Reaction of 3-Arylsydnone-4-Carbohydroximic Acid Chlorides with Active Methylene Compounds (II)

In the presence of triethylamine, 3-arylsydnone-4-carbohydroximic acid chlorides react not only with active methylene compounds containing keto groups to give 3-aryl-4-(4′,5′-disubstituted-isoxazol-3′-yl)sydnones, but also with compounds containing cyano groups to produce 3-aryl-4-(4′-substituted-5′-aminoisoxazol-3′-yl)sydnones or 3-aryl-4-(4′-cyano-5′-substituted-isoxazol-3′-yl)sydnones.