Abstract
A novel and efficient protocol has been developed for the synthesis of various spiro-5-cyanopyrimidines via the three-component condensation of cyclic ketones, nitrile derivatives, and thiourea or urea in ethanol at 60 °C using K
2
CO
3
as catalyst under ultrasonic irradiation. In comparison to conventional methods, high yields, easy work-up, and short reaction times are advantages of this sonocatalyzed procedure. The effects of the catalyst, solvent, and temperature were examined.
Graphical abstract
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