Synthesis of pyrazolo- and [1,2,4]triazolo-[1,5-a]quinolin-9-ols by cycloaddition to 8-hydroxyquinoline N-imide

The reaction of 1-amino-8-hydroxyquinolinium mesitylenesulfonate with alkenes and alkynes containing electron-withdrawing substituents was performed in MeCN-K2C?(3) system and gave the respective 9-hydroxypyrazolo[1,5-a]quinolines. The reaction with acetonitrile\ and aromatic nitriles in aqueous 2 N K?H solution gave the respective 2-substituted 9-hydroxy[1,2,4]triazolo[1,5-a]quinolines.