A New Amphiphilic Brønsted Acid as Catalyst for the Friedel-Crafts Reactions of Indoles in Water
作者:Yuan Cheng、Xiongyu Ou、Jimei Ma、Linhao Sun、Zhong-Hua Ma
DOI:10.1002/ejoc.201801612
日期:2019.1.10
A designed Brønsted acid enables Friedel–Crafts alkylation of indoles in water, whose hydrophobic aggregations of fluorocarbon chains, along with phenyl ring, protected acid sites from bulk water and enriched the substrates. The amphiphilic structure has been proven crucial for the high catalytic efficiency.
Herein, we demonstrated Mn-catalyzed selective C-3 functionalization of indoles with alcohols. The developed catalyst can also furnish bis(indolyl)methanes from the same set of substrates under slightly modified reaction conditions. Mechanistic studies reveal that the C-3 functionalization of indoles is going via a borrowing hydrogen pathway. To highlight the practical utility, a diverse range of substrates
Oxidative Coupling of Benzylamines with Indoles in Aqueous Medium to Realize Bis‐(Indolyl)Methanes Using a Water‐Soluble Cobalt Catalyst and Air as the Oxidant
作者:Parul Saini、Pratishtha Kumari、Susanta Hazra、Anil J. Elias
DOI:10.1002/asia.201901313
日期:2019.12.2
Oxidativecoupling of benzylamines with indoles to bis-(indolyl)methanes (BIMs) was achieved using an inexpensive water-soluble cobalt complex, Co(bpb). The catalyst was found to be quite effective when air was used as the oxidant and water as solvent under mild reaction conditions. Aromatic amines were successfully converted to the corresponding BIMs with yields up to 85 %. We have successfully carried
Pd-catalyzed C–H activation in water: synthesis of bis(indolyl)methanes from indoles and benzyl alcohols
作者:Hidemasa Hikawa、Yuusaku Yokoyama
DOI:10.1039/c2ra21887a
日期:——
A method for the synthesis of bis(indolyl)methanes via palladium-catalyzed domino reactions of indoles with benzyl alcohols was developed. This protocol involves C3-benzylation of indoles and benzylic C–H functionalization in water.
A facile and efficient protocol for the synthesis of C3‐substituted indole derivatives has been developed under mild condition. The iron‐containing ionicliquid, 1‐(2‐hydroxyethyl)‐1,4‐diazabicyclo[2.2.2] octanylium tetrachloroferrate ([Dabco‐C2OH][FeCl4]) as a recyclable catalyst has been successfully used in the synthesis of trisindolines, bis(3‐indolyl) methanes and β‐indolyl alcohols for the first