Electrosynthesis of Dihydropyrano[4,3‐
<i>b</i>
]indoles Based on a Double Oxidative [3+3] Cycloaddition
作者:Subin Choi、Jinhwi Park、Eunsoo Yu、Jeongwoo Sim、Cheol‐Min Park
DOI:10.1002/anie.202003364
日期:2020.7.13
methylene compounds followed by tandem 6π‐electrocyclization leading to the synthesis of dihydropyrano[4,3‐b ]indoles and 2,3‐dihydrofurans. The radical–radical cross‐coupling of the radical species generated by anodic oxidation combined with the cathodic generation of the base from O2 allows for mild reaction conditions for the synthesis of structurally complex heterocycles.
氧化性[3 + 3]环加成反应为六元环形成提供了一条有效途径。该方法是基于吲哚/烯胺与活性亚甲基化合物的电化学氧化偶联,然后串联6π-电环化反应生成二氢吡喃并[4,3- b ]吲哚和2,3-二氢呋喃而实现的。阳极氧化产生的自由基与自由基从O 2产生的自由基之间的自由基交叉偶联为合成结构复杂的杂环提供了温和的反应条件。
Metal-Free Synthesis of Indolopyrans and 2,3-Dihydrofurans Based on Tandem Oxidative Cycloaddition
作者:Subin Choi、Hyeonji Oh、Jeongwoo Sim、Eunsoo Yu、Seunghoon Shin、Cheol-Min Park
DOI:10.1021/acs.orglett.0c01896
日期:2020.7.17
transfer between coupling partners followed by cage collapse allows highly selective cross-coupling while employing only equimolar amounts of coupling partners. Moreover, the mechanistic manifold was expanded for the functionalization of enamines to give the stereoselective synthesis of 2,3-dihydrofurans. This iodine-mediatedoxidative coupling features mild conditions and fast reaction kinetics.
A sustainable C–H functionalization of indoles, pyrroles and furans under a blue LED with iodonium ylides
作者:Saibal Sar、Ranajit Das、Dhiraj Barman、Pikaso Latua、Souvik Guha、Ludovic Gremaud、Subhabrata Sen
DOI:10.1039/d1ob01219c
日期:——
Pyrrole and indole derivatives are functionalized via a green initiative with the dimethylmalonate derived phenyl iodonium ylide 4a in the presence of a blue LED via C–H functionalization of the respective heterocycles in methanol to generate the desired compounds 5–7 in moderate to good yields. Control experiments provide insight into the probable reaction mechanism. Finally, the strategy is successfully
吡咯和吲哚衍生物通过绿色倡议与丙二酸二甲酯衍生的苯基碘鎓叶立德4a在蓝色 LED 存在下通过甲醇中各自杂环的 C-H 官能化进行官能化,以中等至良好的产率生成所需的化合物5-7 . 对照实验提供了对可能反应机制的深入了解。最后,该策略成功应用于azepino[4,5- b ]indole 12a / b的生成。