Step-wise, tandem and one-pot syntheses of 2-(4-oxo-3,4- dihydroquinazolin-2-yl)-N-arylbenzamidesin water - A green protocol

B. Surya Narayana and Ch. Venkata Ramana Reddy

Department of Chemistry, Jawaharlal Nehru Technological University Hyderabad, Kukatpally, Hyderabad (T.S), India - 500 085.


Background: Eco-friendly, one-pot three-component syntheses of 2-(4- oxo-3,4-dihydroquinazolin-2-yl)-N-aryllbenzamides have been developed by combining Di-methyl phthalate with anilines & anthranilamide in water without any catalyst. The reactions involve easy workup, provide excellent yields and use water as solvent making them a green protocol.

Results: As illustrated in Scheme 1, a mixture of Di-methyl phthalate 1, aniline 2a and anthranilamide 3 was refluxed in water for 90 min resulting in the formation of 2 -(4-oxo-3,4-dihydroquinazolin-2-yl)-N-phenylbenzamide 4a i.e 4, R= H (Scheme 1). The structure of the product was assigned on the basis of its spectral properties.

Conclusion: A green synthetic method have been developed for the synthesis of 4a-4i in water through one-pot, three-component synthesis. Significant rate acceleration of the reaction in water observed and compared to the commonly used green solvents.

Keywords :water, Di-methyl phthalate, anilines, anthranilamide, 2-(4- oxo-3,4-dihydroquinazolin-2-yl)-N-phenylbenzamide.