Microwave-assisted ammonium formate-mediated knoevenagel reaction under solvent-free conditions - A green method for C-C bond formation

Abstract

Syntheses of structurally varied densely functionalized olefins have been accomplished (23 examples) through microwave-assisted ammonium formate-mediated Knoevenagel condensation of differently substituted aromatic aldehydes with ethyl cyanoacetate, cyanoacetamide, malononitrile, and malonic acid under solvent-free condition in good yield (76-95%) and high purity. The said reactions occur within very short period of time (0.75-3 min) in eco-friendly conditions involving an operationally simple procedure, eliminating any kind of inorganic support, toxic reagent and organic solvent.