A novel protocol for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones from 2-aminobenzamides and aldehyde derivatives catalyzed by KOH/DMSO suspension has been developed. The present transition metal free methodology is operationally simple, scalable and varieties of 2,3-dihydroquinazolin-4(1H)-one derivatives were obtained in good to excellent yields in short reaction times.
A modified Friedländer conversion of the cyclocondensation of aromatic o‐aminonitriles with carbonyl compounds was discovered. Systematic studies reveal that both the new transformation and the classic Friedländer annulation in the presence of ZnCl2 constitute a pair of divergent reaction, and thecontrolled PDF transformation of this divergent reaction was achieved in the present of bases.