Investigation of Straightforward, Photoinduced Alkylations of Electron‐Rich Heterocompounds with Electron‐Deficient Alkyl Bromides in the Sole Presence of 2,6‐Lutidine
photosensitizer: We introduce a method for selective photoinduced alkylations of electron‐rich heterocompounds with electron‐deficient allylbromides in the presence of 2,6‐lutidine at 365 or 405 nm. Mechanistic investigations reveal that a colored intermediate formed from 2,6‐lutidine and alkyl bromide is involved in the photoactivation. Our approach uses commercially available reagents and a straightforward
C–H functionalization of indoles. The reaction affords 2,3-difunctionalized indoles in up to 84% yield, but the reaction rate depends strongly on electronicsubstituenteffects. Mechanistic DFT studies and control experiments suggest that the secondary functionalization occurs through an independent photocatalytic oxidation of bromide ions formed during the reaction to generate molecular bromine capable
Visible light/Ir(III) photocatalytic initiation of xanthate-based radical-chain reactions: Xanthate group transfer and oxidative addition to aromatic systems
作者:Pedro López-Mendoza、John E. Díaz、Alix E. Loaiza、Luis D. Miranda
DOI:10.1016/j.tet.2018.04.079
日期:2018.9
The protocol can be used in classical xanthate-based inter- and intra-molecular group transfer reactions and oxidative radical addition to several heteroaromatic systems. The process does not require high temperature and reactions are cleaner compared with the traditional peroxide initiation. In the oxidative addition to aromatic systems, the oxidation process is part of the catalytic cycle and does
Blue LED Mediated C-H and N-H Insertion of Indoles into Aryldiazoesters and Iodonium Ylides
作者:Ludovic Gremaud、Subhabrata Sen
DOI:10.2533/chimia.2022.483
日期:——
mediated C-H and N-H insertion reaction in indoles and related heterocycles with aryl diazoesters and iodonium ylides as sources of carbenes. Blue LED effectively facilitates these conversions and was optimized from the option of numerous other LED lights. No metal catalysts were required. The reactions provide formation of differently alkylated indoles, pyrroles and furans. Control experiments and DFT
在此,我们讨论了与蓝色 LED 介导的吲哚和相关杂环中 CH 和 NH 插入反应相关的项目,其中芳基重氮酯和碘鎓叶立德作为卡宾来源。蓝色 LED 有效地促进了这些转换,并从众多其他 LED 灯的选项中进行了优化。不需要金属催化剂。该反应形成不同烷基化的吲哚、吡咯和呋喃。使用对照实验和DFT计算来了解反应机理。作为应用化合物,由烷基化产物合成了带有氮杂[4, 5-b]吲哚和螺哌啶基吲哚结构单元的化合物。