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Using 2-(2-aminophenyl)quinazolin-4(3 H)-one and 2-(2-phenylethynyl)benzaldehyde as the reactants, silver triflate (AgOTf) was proved to be an efficient catalyst to promote not only quinazoline cyclization, but also the intramolecular hydroamination of alkyne for the synthesis of 6-aryl-17 H ,18a H -isoquinolino[2,1- a ]quinazolino[3,2- c ]quinazolin-17-one derivatives in high yields. [ABSTRACT FROM AUTHOR]

A one-pot procedure for the synthesis of 5-benzoyl-8 H -phthalazino[1,2- b ]quinazolin-8-ones is achieved by an iodine-catalyzed reaction of 2-aminobenzohydrazides and 2-alkynylbenzaldehydes in good yields. The salient feature of this strategy is a domino type process including a condensation, addition, hydroamination, and a noteworthy benzyl automatic oxidation by oxygen under metal-catalyst-free conditions. [ABSTRACT FROM AUTHOR]

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]

The iodine-catalyzed reaction of 2-amino- N′-arylbenzohydrazides and haloketones was carried out in ionic liquids and was found in good chemoselectivity. 5-Chloropentan-2-one selectively gave fused pyrrolo[1,2- a]quinazolin-5(1 H)-one derivatives, and 6-chlorohexan-2-one only formed simple quinazolin-4(1 H)-ones, while the second cyclization did not take place at all. Graphical Abstract: [ABSTRACT FROM AUTHOR]

2-(1 H-benzo[ d]imidazol-2-yl)anilines reacted with haloketones including 5-chloropentan-2-one and 6-chlorohexan-2-one catalyzed by iodine, giving benzo[4,5]imidazo[1,2- c]pyrrolo[1,2- a]quinazoline and 6 H-benzo[4,5]imidazo[1,2- c]pyrido[1,2- a]quinazoline derivatives, respectively. This domino-type reaction formed two new heterocycles and three new covalent bonds in one-pot procedure and provided a green method for the synthesis of fused pentacyclic heterocycles bearing both quinazoline and benzimidazole moieties in ionic liquids. [ABSTRACT FROM AUTHOR]

Isoindolo[1,2- b ]quinazolines was obtained in high yields from a reaction between 2-(2-aminobenzamido)malonate and 2-bromobenzaldehyde catalyzed by CuI under Pd and ligand-free conditions. • It is an α -arylation catalyzed by CuI under ligand-free conditions. • The three new bonds and two new heterocycle are formed. • It is a tandem cyclization reaction to fused tetracyclic isoindolo[1,2- b ]quinazolines. A tandem cyclization reaction of diethyl 2-(2-aminobenzamido)malonates and 2-bromobenzaldehydes was developed for the synthesis of isoindolo[1,2- b ]quinazoline derivatives. The quinazoline was formed first catalyzed by CuI, followed by a noteworthy α -arylation reaction under Pd and ligand-free conditions in the presence of Cs 2 CO 3. [ABSTRACT FROM AUTHOR]