Herein, the synthesis of an inexpensive and biodegradable Lewis acidic ionic liquid by using choline chloride and ZnCl 2 and its application in the synthesis of 6-amino-4-alkyl/aryl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles is reported. In this reaction, various aldehydes were reacted with malononitrile, ethyl acetoacetate and hydrazine hydrate to afford the corresponding products in high yields. All of the reactions were carried out in both room temperature and in 90 °C. The advantage of this ionic liquid was its application for acid sensitive heterocycles, which yielded the corresponding 6-amino-4-alkyl/aryl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles without any by-products. In the second project, N -methyl-2-pyrrolidonum hydrogen sulfate [H-NMP]HSO 4 was synthezised and its application as an acidic catalyst with high acid strength for synthesis of 6-amino-4-alkyl/aryl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles was investigated. Various aldehydes were reacted with malononitrile, ethyl acetoacetate and hydrazine hydrate to afford the corresponding products in high yields. All of the reactions were done under both room temperature and 90 °C conditions.