One-pot synthesis of fully substituted 1,3,4-oxadiazole derivatives from aromatic carboxylic acids, cyclobutanone and N-isocyaniminotriphenylphosphorane

摘要

Reactions of N-isocyaniminotriphenylphosphorane withcyclobutanone in the presence of aromatic (or heteroaromatic)carboxylic acids proceeded smoothly at room temperature and in neutralconditions to afford sterically congested 1-(5-aryl-1,3,4-oxadiazol-2-yl)-1-cyclobutanol derivatives in high yields. The reaction proceededsmoothly and cleanly under mild conditions and no side reactions wereobserved. The structures of the products were deduced from their IR,^1HNMR, and ^{13}CNMR spectra, and mass spectrometry.