Marzieh Cheraghipoor - Department of Chemistry, University of Sistan and Baluchestan, P.O. Box ۹۸۱۳۵-۶۷۴, Zahedan, Iran
Malek Taher Maghsoodlou - Department of Chemistry, University of Sistan and Baluchestan, P.O. Box ۹۸۱۳۵-۶۷۴, Zahedan, Iran
Davod Mohebbi-Kalhori - Department of Chemistry, University of Sistan and Baluchestan, P.O. Box ۹۸۱۳۵-۶۷۴, Zahedan, Iran
Mohammad Reza Faghihi - Department of Chemistry, University of Sistan and Baluchestan, P.O. Box ۹۸۱۳۵-۶۷۴, Zahedan, Iran

With increasing interest in green chemistry, the development of new eco-friendly methods such as one-pot multicomponent reactions (MCRs) with using recyclable heterogeneous catalysts has been raised. In this study, the catalytic activity of SnO2 based nano thin-films which prepared by spray pyrolysis technique on the inside of beakers has been reported for one-pot synthesis of dihydropyrano[2,3-c]pyrazoles. This catalyst is found to be efficient heterogeneous catalysts for the multicomponent reaction of 3-methyl-1-phenyl-2-pyrazolin-5-one/hydrazine monohydrate, ethyl acetoacetate with malononitrile and aryl aldehydes. The results confirm that SnO2 nano-thin films are a potential catalytic compound for synthesis relevant to pyrazole scaffolds in high yields. Catalyst being heterogeneous lead to reused several times without a significant decrease of catalytic activity, which is in agreement with the principles of green chemistry. SnO2 nano-thin films were developed as an efficient catalyst for the greener synthesis of dihydropyrano[2,3-c]pyrazoles in high yields without any troublous by-products, besides the ease of work-up and purification[1-3].