Efficient Synthesis of Benzo[b]pyrans and Knoevenagel Products Using Magnetically Separable Nano TPPA-IL-Fe۳O۴

A simple, efficient, and green practical approach to Knoevenagel condensation of malononitrile and different aldehydes has been developed using an ionic liquid functionalized on Fe۳O۴ magnetic nanoparticles as heterogeneous catalyst. This nanostructural catalyst has also been applied for the synthesis of ۴H-benzo[b]pyran derivatives in water at room temperature in short reaction time. All of the products were obtained in good to excellent yields. The TPPA-IL-Fe۳O۴ catalyst was used at least seven times with comparable activities to the fresh catalyst.

Keywords:

Ionic Liquid , Fe۳O۴ magnetic nanoparticles , Knoevenagel condensation , ۴H-benzo[b]pyran