Synthesis of Indoles by Reductive Cyclization of Nitro Compounds Using Formate Esters as CO Surrogates
作者:Manar Ahmed Fouad、Francesco Ferretti、Dario Formenti、Fabio Milani、Fabio Ragaini
DOI:10.1002/ejoc.202100789
日期:2021.9.14
A very efficient, general and scalable protocol for the preparation of indoles and other N-heterocycles from suitably substituted nitroarenes using alkyl and phenyl formates as CO surrogates was described. Using phenyl formate, the products were isolated in yields often higher than those previously achieved by using gaseous CO. The mechanism of both the decarbonylation reaction of phenyl formate and
描述了使用烷基和苯基甲酸酯作为 CO 替代物从适当取代的硝基芳烃制备吲哚和其他N-杂环的非常有效、通用和可扩展的方案。使用甲酸苯酯,产物的分离产率通常高于以前使用气态 CO 实现的产率。通过动力学和机理研究阐明了甲酸苯酯的脱羰反应和环化反应的机理。
Pd‐Catalyzed Reductive Cyclization of Nitroarenes with CO
<sub>2</sub>
as the CO Source
作者:Xinyu Guan、Haoran Zhu、Yingwei Zhao、Tom G. Driver
DOI:10.1002/ejoc.201901629
日期:2020.1.9
A practical, broad‐scope reductive amination process that constructs N‐heterocycles from nitroarenes was developed that uses CO2 as the source of CO.
Counterion Control of
<i>t</i>
‐BuO‐Mediated Single Electron Transfer to Nitrostilbenes to Construct
<i>N</i>
‐Hydroxyindoles or Oxindoles
作者:Yingwei Zhao、Haoran Zhu、Siyoung Sung、Donald J. Wink、Joseph M. Zadrozny、Tom G. Driver
DOI:10.1002/anie.202104319
日期:2021.8.23
tert-Butoxide unlocks new reactivity patterns embedded in nitroarenes. Exposure of nitrostilbenes to sodium tert-butoxide was found to produce N-hydroxyindoles at room temperature without an additive. Changing the counterion to potassium changed the reaction outcome to yield solely oxindoles through an unprecedented dioxygen-transfer reaction followed by a 1,2-phenyl migration. Mechanistic experiments