Synthesis of coumarins and 2,3-dihydroquinazolin-4(1H)-ones using trichloroacetic acid as a catalyst.

Trichloroacetic acid was used as an efficient catalyst for the synthesis of coumarins from phenols and beta-ketoesters and in an efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones through the condensation of 2-aminobenzamide with aldehydes or ketones under solvent-free conditions. The remarkable advantages offered by this method are short reaction times, simple procedure, and an easy work-up without using any chromatographic methods.