Diethyl Phosphate‐Catalyzed One‐Pot Synthesis of 2,3‐Dihydroquinolin‐4(1 <i>H</i> )‐ones from 2‐Aminoacetophenones and Benzaldehydes

Abstract A diethyl phosphate (DEP)‐catalyzed one‐pot synthesis of 2,3‐dihydroquinolin‐4(1 H )‐ones in DMF was achieved. Control experiments led to a plausible mechanism involving an intermolecular aldol condensation of 2‐aminoacetophenone and aldehyde, followed by a hydrogen bond‐driven cyclization. In this process, a series of 2,3‐dihydroquinolin‐4(1 H )‐ones were obtained in good yields (48–84%). This strategy features transition metal‐free and short reaction times.