Abstract
Uncatalyzed Knoevenagel condensation reaction between active methylene compound dimedone (1) and various aromatic/heteroaromatic aldehydes such as 3-pyridinylcarboxaldehyde (2d) in an absolute aqueous condition has been investigated. The reaction performed in a minimum amount of distilled water at boiling temperature provided corresponding arylidene/heteroaromatic derivatives with good purity in high yield. The method is operationally simple, less time consuming and involves eco-friendly conditions. In addition, a model compound was synthesized using various known catalysts under the optimized condition and solvents to compare the results of catalyzed and uncatalyzed reactions.
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