Catalysis by L-Lysine: A Green Method for the Condensation of Aromatic Aldehydes with Acidic Methylene Compounds in Water at Room Temperature

The condensation of aromatic aldehydes with acidic methylene compounds such as ethyl benzoylacetate, 2,4‐pentanedione and dimedone proceeded efficiently in pure water in the presence of L‐lysine at room temperature. Interestingly, there are two different reaction mechanisms taking place under the same green catalyst system. This provides a green and mild synthetic method for the preparation of these two classes of compounds. The condensation of aromatic aldehydes with acidic methylene compounds such as ethyl benzoylacetate, 2,4‐pentanedione and dimedone proceeded efficiently in pure water in the presence of L‐lysine at room temperature. Interestingly, there are two different reaction mechanisms taking place under the same green catalyst system. This provides a green and mild synthetic method for the preparation of these two classes of compounds.