Catalysis by Amberlyst A-21: A Greener Approach to 4,5,6,7-Tetrahydro-1H-indazol-3(2H)-ones via Construction of Cyclohexanones.

The title compounds (III) are obtained via a two-step one-pot synthesis involving the construction of the cyclohexanone ring from aromatic aldehydes and β-ketoesters as initial step under mild reaction conditions.