Application of the ultrasound in the mild synthesis of substituted 2,3-dihydroquinazolin-4(1H)-ones catalyzed by heterogeneous metal–MWCNTs nanocomposites

A practical method were applied successfully to synthesize mono- and disubstituted dihydroquinazolinones through three-component condensation of isatoic anhydride, primary amines or ammonium acetate with aromatic aldehydes in the presence of some transition metals–multi-walled carbon nanotubes under sonication. Also, metals supported on MWCNTs showed excellent catalytic performance for above-mentioned condensation. This methodology provides general, easy and efficient approach to afford the corresponding aryl substituted quinazolinone derivatives using mentioned nanocomposites as catalyst under sonication in excellent yields. The advantages of present protocol are convenient reaction, simple work-up, greenness, energy efficiency and reusable catalyst as well as mild reaction conditions. The employed metal–MWCNTs catalysts are heterogeneous and recyclable, that make the process more environmentally friendly.