We report herein an effective method for the halogenation of imidazo-fused heterocycles using readily available sodiumsalts (NaCl/NaBr/NaI) as halogen source and K2S2O8 (or) oxone as promoter. A variety of C-3 halogenated imidazo[1,2-a]pyridines and benzo[d]imidazo[2,1-b]thiazoles were obtained in good to excellent yields. The present method of halogenation has been also extended to 2-aminopyridines
我们在此报告了一种使用容易获得的钠盐(NaCl / NaBr / NaI)作为卤素源和K 2 S 2 O 8(或)oxone作为促进剂的咪唑基稠合杂环卤化的有效方法。以良好或优异的产率获得了各种C-3卤代咪唑并[1,2- a ]吡啶和苯并[d]咪唑并[2,1- b ]噻唑。本发明的卤化方法还以中等至优异的产率扩展到2-氨基吡啶,2-氨基嘧啶,吲哚和异喹啉。
Metal-free regioselective bromination of imidazo-heteroarenes: the dual role of an organic bromide salt in electrocatalysis
作者:Partha Pratim Sen、Vishal Jyoti Roy、Sudipta Raha Roy
DOI:10.1039/d1gc01069g
日期:——
tetra-n-butylammonium bromide (TBAB), as a brominating agent and as an electrolyte for the regioselective bromination of several imidazo heteroaromatic motifs. Instead of using a transition metal/external oxidant, this methodology utilized electron holes and electrons by means of anodic oxidation and cathodic reduction to form the desired products in good to excellent yields at ambient temperature. The method is simple
pharmacologically relevant lead structures. A highly flexible synthetic procedure was developed, derived from investigations of the influence of the substrates, solvents, ligand systems, and side reactions.
Electrochemical Activation of the C–X Bond on Demand: Access to the Atom Economic Group Transfer Reaction Triggered by Noncovalent Interaction
作者:Partha Pratim Sen、Vishal Jyoti Roy、Sudipta Raha Roy
DOI:10.1021/acs.joc.2c00529
日期:2022.8.5
demonstrates the involvement of noncovalentinteraction via hydrogen or halogenbondinginteraction in triggering paired electrolysis for the group transfer reactions. Specifically, this method demonstrated the bromination of several aromatic and heteroaromatic compounds through the activation of the C(sp3)–Br bond of organic–bromo derivatives on demand. This electrochemical protocol is mild, and mostly