Nano-CuCr2O4: An Efficient Catalyst for a One-Pot Synthesis of Tetrahydrodipyrazolopyridine

The efficient synthesis of eleven tetrahydrodipyrazolopyridines (two of which are novel) has been achieved by the multicomponent condensation reaction of ethyl acetoacetate, an araldehyde, hydrazine hydrate and ammonium acetate at room temperature in ethanol in the presence of nano-CuCr2O4. The key advantages of this process are good to high yields, short reaction times, practical simplicity, reusability of the catalyst and low catalyst loading.