Tandem Knoevenagel–Michael–cyclocondensation reaction of malononitrile, various aldehydes and 2-naphthol over acetic acid functionalized ionic liquid.

Highlights: [•] Introducing efficient catalysts for the synthesis of 2-amino benzo[h]chromenes. [•] Study of TGA, XRD and calculation of size and inter planer distance of the catalysts. [•] Generality of the catalysts, high yields and short reaction times. [ABSTRACT FROM AUTHOR]