Turkish Journal of Chemistry, Vol.38, No.4, 650-660, 2014
Aqueous DABCO,an efficient medium for rapid organocatalyzed Knoevenagel condensation and the Gewald reaction
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.