Selenium-Catalyzed Oxidative C−H Amination of (E)‑3-(Arylamino)-2-styrylquinazolin-4(3H)‑ones: A Metal-Free Synthesis of 1,2-Diarylpyrazolo[5,1‑b]quinazolin-9(1H)‑ones

Yetong Zhang, Yinlin Shao,* Julin Gong, Jianghe Zhu, Tianxing Cheng, and Jiuxi Chen*

Abstract：A novel metal-free catalysis protocol for the synthesis of 1,2-diarylpyrazolo[5,1-b]quinazolin-9(1H)-ones via intramolecular oxidative C−H amination of (E)-3- (arylamino)-2-styrylquinazolin-4(3H)-ones has been developed in moderate to good yield. The method shows good functional group tolerance. The presented approach offers a new synthetic pathway toward the core structures of 2,3-fused quinazolinones. Moreover, the present synthetic route can be readily scaled up to gram quantity without difficulty. A possible mechanism involves a seleniranium ion followed by threemembered ring opening to form the C−N bond.

原文链接： https://doi.org/10.1021/acs.joc.8b03179