关键词: 可见光催化, 咖啡因, 自由基反应, 二氟甲基化

Abstract: Visible light catalysis offers several advantages, including mild reaction conditions, high efficiency, low energy consumption, and broad functional group compatibility, making it a powerful tool in synthetic chemistry. Nitrogen-containing heterocyclic frameworks and fluorinated functional groups are widely present in bioactive molecules. Selectively introducing a difluoromethyl group (CF₂H) into nitrogen heterocycles can significantly influence the pharmacological and pharmacokinetic properties of lead drug candidates. This paper reports a visible light-mediated radical difluoromethylation of caffeine, employing [bis(difluoroacetoxy)iodo]benzene as the difluoromethylating reagent. The reaction proceeds without the need for transition metals or oxidants, is straightforward to perform, and easy for students to learn, offering both educational and practical value.

Key words: Visible light catalysis, Caffeine, Radical reaction, Difluoromethylation