Synthesis of 2<i>H</i>-Indazoles by the [3 + 2] Cycloaddition of Arynes and Sydnones

Abstract

A rapid and efficient synthesis of 2H-indazoles has been developed, which involves the [3 + 2] dipolar cycloaddition of arynes and sydnones. The process proceeds under mild reaction conditions in good to excellent yields.