Visible‐Light‐Induced Metal‐Free Synthesis of 2‐Phosphorylated Thioflavones in Water

• Published in: ChemSusChem Vol. 13; no. 2; pp. 298 - 303
• Main Authors: Liu, Xiao‐Ceng, Chen, Xiao‐Lan, Liu, Yan, Sun, Kai, Peng, Yu‐Yu, Qu, Ling‐Bo, Yu, Bing
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 19.01.2020
• Subjects: Ambient temperature; aqueous reaction; Aqueous solutions; Functional groups; Light irradiation; metal-free; Phosphines; phosphorylation; photocatalysis; Recyclability; thioflavones; aqueous reaction; photocatalysis; metal-free; phosphorylation; thioflavones
• ISSN: 1864-5631; 1864-564X; 1864-564X
• DOI: 10.1002/cssc.201902817

The introduction of phosphorus functional groups into the skeleton of thioflavones is an attractive task and of great significance. Herein, a metal‐free visible‐light‐induced radical cascade cyclization was developed for the preparation of 2‐phosphorylated thioflavones from methylthiolated alkynones and phosphine oxides. In water as a green reaction medium, a large number of such 2‐phosphorylated thioflavones were prepared, catalyzed by 4CzIPN [1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene] under visible‐light irradiation. These reactions could be performed at ambient temperature and feature simple operation, wide reaction scope, and recyclability of aqueous media. Let there be light: By using water as a reaction medium, a large number of 2‐phosphorylated thioflavones are prepared through the reaction of methylthiolated alkynones and phosphine oxides catalyzed by 4CzIPN [1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene] under visible‐light irradiation.