Visible-Light-Induced Divergent C-H Esterification/Alkylation of Quinoxalin-2(1H)-ones with Aldehydes under Mild
1College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Zhejiang Key Laboratory of Organosilicon Material Technology, Hangzhou Normal University, Hangzhou 311121, China.
Abstract:
Herein, we introduce an efficient and straightforward strategy for the selective C-H esterification and alkylation of quinoxalin-2(1H)-ones with aldehydes. A key feature of our study is the ability to perform both C-H esterification and alkylation using different types of aldehydes. The reaction system is highly compatible with a range of quinoxalin-2(1H)-ones and aldehydes, yielding C3-esterified and C3-alkylated products in moderate-to-good yields. The applicability of this approach is further enhanced by its scalability through continuous-flow synthesis, late-stage modification of significant molecules, and product derivatization. Our mechanistic investigations reveal a radical relay mechanism, triggered by a hydrogen atom transfer process.
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