One-pot, Three-component Synthesis of Fully Substituted 1,3,4-Oxadiazole Derivatives from (N-Isocyanoimino)triphenylphosphorane, Aromatic Carboxylic acids and (1R)-(-)-Campherchinon

Abstract

Young Researchers Club, Zanjan Branch, Islamic Azad University, Zanjan, IranReceived October 28, 2011, Accepted November 29, 2011Reactions of ( N-isocyanimino)triphenylphosphorane with (1 R)-(−)-campherchinon in the presence of aromaticcarboxylic acids proceed smoothly at room temperature and in neutral conditions to afford sterically congested1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditionsand no side reactions were observed.Key Words : (N-Isocyanimino)triphenylphosphorane, (1R)-(−)-Campherchinon, Aromatic carboxylic acid,1,3,4-Oxadiazole, aza-Wittig reactionIntroductionMulticomponent reactions (MCR) have appeared as anefficient and powerful tool in modern synthetic organicchemistry due to their valued features such as atom economy,straightforward reaction design, and the opportunity toconstruct target compounds by the introduction of severaldiversity elements in a single chemical event. Since all theorganic reagents employed are consumed and incorporatedinto the target compound, purification of products resultingfrom MCR is also simple.