effective and convenient synthesis of 2-amino-4h-chromenes promoted by melamine as a recyclable organocatalyst

This study focused on the applicability of melamine as a cheap and efficient organocatalyst in the acceleration of the synthesis of 4-aryl-4h-chromenes derivatives. under the selected conditions, a wide range of aldehydes readily underwent condensation with activated phenols and malononitrile to afford the high to excellent yields. also, organocatalyst was used for the synthesis of 2-amino-5,10-dioxo-5,10-dihydro-4hbenzo[g]chromenes by the reaction of aromatic aldehydes, malononitrile and 2-hydroxynaphthalene-1,4-dione in refluxing h2o:etoh. this method provides several advantages such as convenient work-up, mild reaction conditions, use of an inexpensive and readily available catalyst, short reaction times, high yields of the products and reusability of the catalyst.