Organocatalytic Knoevenagel condensations by means of carbamic acid ammonium salts

Org Lett. 2013 Apr 19;15(8):1854-7. doi: 10.1021/ol400462d. Epub 2013 Apr 8.

Abstract

The Knoevenagel condensation between an active methylene compound and an aromatic aldehyde with a carbamic acid ammonium salt used as an organocatalyst gave the desired Knoevenagel products in up to 98% yield. The reaction occurred at rt and in a short reaction time under solvent-free conditions. In addition, no extraction, wash, or chromatography steps were needed to obtain a high-purity Knoevenagel product.