Hypervalent iodine oxidation of 1-phenyl-3-arylpyrazole-4-carboxaldehyde oximes: A facile and efficient synthesis of new 3,4-bis(1-phenyl-3- arylpyrazolyl)-1,2,5-oxadiazole-N-oxides

Abstract

Oxidation of pyrazole-4-carboxaldehyde oximes 2 with iodobenzene diacetate leads to dimerization of initially formed nitrile oxides, thereby offering an easy and efficient method for the synthesis of new 3,4-bis(1-phenyl-3- arylpyrazolyl)-1,2,5-oxadiazole-N-oxides (4). © ARKAT USA, Inc.