DBU-Promoted Formal [4+2] Annulation Reactions of o-Chloromethyl Anilines with Azlactones
Haojie Ji, Chonglong He, Hongjie Gao, Weijun Fu, Jianfeng Xu*
*Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. of China, Email: jfxuzstu.edu.cn
H. Ji, C. He, H. Gao, W. Fu, J. Xu, Synthesis, 2021, 53, 1349-1355.
DOI: 10.1055/s-0040-1706549 (free Supporting Information)
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DBU mediates a formal [4+2] annulation reaction of aza-ortho-quinone methides (generated from o-chloromethyl anilines) with enolates (formed from azlactones) to provide biologically significant 3,4-dihydroquinolin-2(1H)-one derivatives in good yields. This reaction offers use of readily accessible starting materials, broad substrate scope, and mild reaction conditions.
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DBU, [4+2] annulation, aza-ortho-quinone methides, enolates, 3,4-dihydroquinolin-2(1H)-ones