Zhang Yetong, Shao Yinlin, Gong Julin, Zhu Jianghe, Cheng Tianxing, Chen Jiuxi
College of Chemistry & Materials Engineering , Wenzhou University , Wenzhou 325035 , China.
J Org Chem. 2019 Mar 1;84(5):2798-2807. doi: 10.1021/acs.joc.8b03179. Epub 2019 Feb 18.
A novel metal-free catalysis protocol for the synthesis of 1,2-diarylpyrazolo[5,1- b]quinazolin-9(1 H)-ones via intramolecular oxidative C-H amination of ( E)-3-(arylamino)-2-styrylquinazolin-4(3 H)-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 three-membered ring opening to form the C-N bond.
已开发出一种新型无金属催化方案，通过（E）-3-（芳基氨基）-2-苯乙烯基喹唑啉-4（3H）-酮的分子内氧化C-H胺化反应合成1,2-二芳基吡唑并[5,1-b]喹唑啉-9（1H）-酮，产率中等至良好。该方法显示出良好的官能团耐受性。所提出的方法为2,3-稠合喹唑啉酮的核心结构提供了一条新的合成途径。此外，目前的合成路线可以很容易地扩大到克级规模，没有困难。一种可能的机理涉及一个硒鎓离子，随后三元环开环形成C-N键。
