Bi Bi Fatemeh Mirjalili - Yazd University
Maryam Mehravar - Dept. Chemistry, Yazd University
Abdolhamid Bamoniri - Departent of Organic Chemistry, Faculty of Chemistry, University of Kashan
Elaheh Babaei - Department of chemistry, Yazd University

In this research, a high efficient, simply and rapid method was applied for the synthesis of dihydropyrano[۳,۲-c]chromene derivatives by one-pot, three-component condensation of aldehydes, malononitrile and ۴-hydroxycoumarin in H۲O/ethanol (۱:۱ v/v) under reflux conditions. This reaction was run by using nano-silica supported ۱,۵-Diazabicyclo(۴.۳.۰)non-۵-en (DBN) which has been abbreviated as nano-SiO۲/DBN under aqueous condition. The nano-SiO۲/DBN catalyst was synthesized by reaction between silica chloride and DBN. The main advantages of this procedure are high yields, short reaction times and easy work-up. Furthermore, the catalyst could be reused for five times.

Dihydropyrano[۳, ۲-c]chromene, ۴-Hydroxycoumarin, ۱, ۵-Diazabicyclo(۴.۳.۰)non-۵-en, nano-silica, nano-SiO۲/DBN, Aqueous medium