Vanadium-Catalyzed Synthesis of 4(3H)-Quinazolinones from Anthranilamides and Aryl Aldehydes

Abstract

An efficient synthesis of 2-substituted and 2,3-disubstituted quinazolin-4(3H)-ones via tandem reaction of anthranilamides and aromatic aldehydes catalyzed by vanadyl acetylacetonate with 1 mol% loading under an air atmosphere is described. This new method is associated with several advantages such as low catalyst loading (only 1 mol%), use of green oxidant in the form of air, high atom economy, and good to excellent yields. A mechanism of vanadium-catalyzed synthesis of 4(3H)-quinazolinones has also been proposed.

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GRAPHICAL ABSTRACT

Keywords:

• Anthranilamides
• aromatic aldehydes
• domino reaction
• quinazolin-4(3H)-ones
• vanadyl acetylacetonate

ACKNOWLEDGMENTS

We thank the National Science Foundation of China (No. 20672088), the Ministry of Human Resources and Social Security of the People's Republic of China (No. ZF0022), the Science and Technology Bureau of Sichuan (No. 2011HH0016), the Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (No. SKLGP2012K005) and the Cultivating Program for Excellent Innovation Team of Chengdu University of Technology (No. HY0084) for providing the necessary financial support. We thank Pinaki Bhadury for his comments.

Notes

^a Reaction conditions: Metal salt (0.01 mmol), anthranilamide (1 mmol), benzaldehyde (1 mmol), and DMA (3 mL), at 120 °C for 15 h, unless otherwise mentioned.

^b Isolated yield.

^c 78 °C.

^d 100 °C.

^a Reaction conditions: VO(acac)₂ (0.01 mmol), anthranilamide (1 mmol), substituted benzaldehyde (1 mmol), and DMA (3 mL), at 120 °C for 15 h.

^b Isolated yield.