The Chemo‐selective Reaction of 2‐Amino‐N′‐arylbenzohydrazide and Ketonic Acid Catalyzed by Iodine for the Synthesis of Quinazoline Derivatives.

The chemo‐selective reaction of 2‐amino‐N′‐arylbenzohydrazide and ketonic acid catalyzed by iodine was used to synthesize various 2,3‐dihydroquinazolin‐4(1H)‐ones efficiently. The use of levulinic acid furnished a series of 2,3,3a,4‐tetrahydropyrrolo[1,2‐a]quinazoline‐1,5‐diones in high yields, while acetobutyric acid only afforded the quinazoline skeletons without forming the second pyridine ring. Using alcohol as the solvent instead of ionic liquids, a subsequent esterification was performed with the carboxylic group of acetobutyric acid substrate in one‐pot manner. [ABSTRACT FROM AUTHOR]