Aqueous DABCO, an efficient medium for rapid organocatalyzed Knoevenagel condensation and the Gewald reaction

Authors: MOHAMMAD SAEED ABAEE, SOMAYEH CHERAGHI

Abstract: In the presence of water and 1,4-diazabicyclo[2.2.2]octane, several aldehydes and cyclic ketones underwent efficient Knoevenagel condensation with malononitrile and ethyl cyanoacetate to produce the respective \alpha.\beta-unsaturated systems within fairly short time periods. As a result, high yields of conjugated products were easily obtained. Products could be engaged in a Gewald reaction, either stepwise or in situ, to produce efficiently their respective 2-aminothiophenes within 4--7 h.

Keywords: Knoevenagel condensation, Gewald reaction, organocatalysis, aqueous conditions, amine

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