Novel, Efficient, and Green Procedure for the Knoevenagel Condensation Catalyzed by Diammonium Hydrogen Phosphate in Water

Abstract

Knoevenagel condensation of various aromatic and heteroaromatic aldehydes with active methylene compounds such as methyl and ethyl cyanoacetate, malononitrile, and cyanoacetamide proceeds smoothly with stirring in water in the presence of 4 mol% of diammonium hydrogen phosphate. The reactions were carried out at room temperature in short periods with a very simple workup procedure and good to high yields.

Keywords:

• Alkene
• diamamonium hydrogen phosphate
• Knoevenagel condensation
• water

Acknowledgments

Saeed Balalaie is grateful to the Alexander von Humboldt foundation for the research fellowship and equipment donation. Partial support of this work by the K. N. Toosi University of Technology Research Council is gratefully acknowledged.