A simple and green method for the four-component synthesis of spiro[indoline-3,4'-pyrano[2,3-c]pyrazole using a new zeolite Y

Mn(II)/Pb(II)-exchanged zeolite Y was synthesized and characterized by XRD, EDX, FT-IR and SEM spectroscopies. This is the first application of Mn/Pb-Y in four-component synthesis of spiro[indoline-3,4'-pyrano[2,3-c]pyrazole from isatin, malononitrile, ethylacetoacetate and hydrazine hydrate as a heterogeneous acidic catalyst. Short reaction times, high yields of products and simple work-up procedure are the advantages of current method. The catalyst is inexpensive, can be easily prepared and can be recovered and reused.Short reaction times, high yields of products and simple work-up procedure are the advantages of current method. The catalyst is inexpensive, can be easily prepared and can be recovered and reused and reused.