[Bmim][CF3COO] as a Solvent and a Catalyst for the Knoevenagel Condensation

A facile and green strategy for the Knoevenagel condensation reaction of aryl aldehydes and active methylene compounds using [Bmim][CF3COO] ionic liquid as a solvent and a catalyst has been introduced. The method features some advantages such as good to excellent yield of products, relatively short reaction time, mild reaction conditions, broad substrate scope, and scalability. Moreover, the ionic liquid solvent could be conveniently recycled and reused up to three times without any considerable loss of catalytic activity. Twelve products were obtained in high yields, and their structures were confirmed by NMR data. A plausible reaction mechanism involving the role of the ionic liquid catalyst was also suggested.