Bargellini Reaction in the Series of NH-Heterocycles

NH-Heterocycles were studied as nucleophiles in Bargellini reaction. It was shown that 5-substituted tetrazoles, 1-substituted tetrazol-5-ones, and 1,2,3-triazoles easily react with chloroform and acetone or cyclopentanone in the presence of NaOH. The effect of the reactant’s nature, their ratio and temperature on the reaction outcome was studied. The presented procedure provides the corresponding derivatives of hindered carboxylic acids in good yields. In the case of 5-substituted tetrazoles the reaction led exclusively to N² isomer.