Logo image
Back
Sodium halides as the source of electrophilic halogens in green synthesis of 3-halo- and 3,n-dihalobenzo[b]thiophenes
Journal article   Peer reviewed

Sodium halides as the source of electrophilic halogens in green synthesis of 3-halo- and 3,n-dihalobenzo[b]thiophenes

Tanay Kesharwani, Cory Kornman, Amanda Tonnaer, Amanda Hayes, Seoyoung Kim, Nikesh Dahal, Ralf Romero and Andrew Royappa
Tetrahedron, Vol.74(24), pp.2973-2984
06/14/2018
DOI: https://doi.org/10.1016/j.tet.2018.04.080
PMCID: PMC6420224
PMID: 30886445
Web of Science ID: WOS:000441482900008

Metrics

15 Record Views
25 Times Cited - Web of Science

Abstract

A convenient methodology for the synthesis of mono- and di-halogenated benzo[b]thiophenes is described herein, which utilizes copper(II) sulfate pentahydrate and various sodium halides in the presence of substituted 2-alkynylthioanisoles. The proposed method is facile, uses ethanol as a green solvent, and results in uniquely substituted benzo[b]thiophene structures with isolated yields up to 96%. The most useful component of this methodology is the selective introduction of bromine atoms at every available position (2-7) around the benzo[b]thiophene ring, while keeping position 3 occupied by a specific halogen atom such as CI, Br or I. Aromatic halogens are useful reactive handles; therefore, the selective introduction of halogens at specific positions would be valuable in the targeted synthesis of bioactive molecules and complex organic materials via metal-catalyzed cross coupling reactions. This work is a novel approach towards the synthesis of dihalo substituted benzo[b]thiophene core structures, which provides a superior alternative to the current methods discussed herein. (C) 2018 Elsevier Ltd. All rights reserved.

Details

Logo image