Abstract
Ultrasound was used to synthesis 3-cyano-8-methyl-2-oxo-4-substituted 1,2,5,6,7,8-hexahydroquinolines in a one-pot multicomponent reaction of the corresponding aldehyde, 2-methylcyclohexanone, and excess ammonium acetate and ethyl cyanoacetate in boiling ethanol. The proposed method is uncomplicated, does not take much time, and provides higher product yield, in contrast to the conventional two-step synthesis involving formation of 2-arylidene-6-methylcyclohexanones via Claisen-Schmidt condensation followed by cyclocondensation with ethyl cyanoacetate and ammonium acetate. The structure of the synthesized compounds was confirmed by IR, H-1 and C-13 NMR spectroscopy and x-ray diffraction.