Aqueous-Medium Carbon–Carbon Bond-Forming Radical Reactions Catalyzed by Excited Rhodamine B as a Metal-Free Organic Dye under Visible Light Irradiation
radical addition–cyclization–trapping reactions under visible light irradiation. In the presence of (i-Pr)2NEt, the electron transfer from the excited rhodamine B to perfluoroalkyl iodides proceeded smoothly to promote the carbon–carbonbond-forming radical reactions in aqueous media. When i-C3F7I was employed as a radical precursor, the aqueous-medium radical reactions proceeded even in the absence of
(i-Pr)2NEt, the photo-induced cascade radical addition–cyclization–trapping reaction proceeded in aqueous media. When i-C3F7I was employed as a radical precursor, the iodine atom-transfer radical cyclization proceeded even in the absence of (i-Pr)2NEt. Under the photo-induced conditions, ICH2CN and ICH2CF3 also worked well as carbon radical precursors. The photo-induced reductive electron-transfer to CF3SO2Cl
在Ru(bpy)3 Cl 2 ·6H 2 O和(i -Pr)2 NEt存在下,光诱导的级联自由基加成-环化-捕集反应在水性介质中进行。当将i -C 3 F 7 I用作自由基前体时,即使不存在(i -Pr)2 NEt ,碘原子转移自由基的环化反应仍在进行。在光诱导条件下,ICH 2 CN和ICH 2 CF 3也可以作为碳自由基的前体。光诱导的还原电子转移至CF 3 SO 2Cl促进了氯原子转移自由基的环化。
Direct Photoinduced Electron Transfer from Excited State of Rhodamine B for Carbon-Radical Generation
The photoinducedelectrontransfer (PIET) from the excited singlet state (S 1) of rhodamine B to i-C3F7I smoothly proceeded in the presence of water. This process was supported by the fluorescence quenching of rhodamine B with addition of i-C3F7I in ethanol. The present method was applied to the atom-transfer radical reaction involving the cyclization step.
在水的存在下,从罗丹明 B 的激发单线态 (S 1) 到 i-C3F7I 的光诱导电子转移 (PIET) 顺利进行。通过在乙醇中加入 i- ,罗丹明 B 的荧光猝灭支持该过程。本方法应用于涉及环化步骤的原子转移自由基反应。
Cascade Radical Reaction Induced by Polarity-Mismatched Perfluoroalkylation