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Letters in Organic Chemistry

Editor-in-Chief

ISSN (Print): 1570-1786
ISSN (Online): 1875-6255

Short Communication

α,α-Dibromoketones as Synthetic Equivalents of α-Bromoketones for the Synthesis of Thiazolo[3,2-a]benzimidazoles

Author(s): Ravi Kumar, Reshmi R Nair, Richa Prakash, Taeho Bae, Toshifumi Dohi* and Om Prakash*

Volume 21, Issue 2, 2024

Published on: 09 October, 2023

Page: [209 - 212] Pages: 4

DOI: 10.2174/1570178620666230803123511

Price: $65

Abstract

Utilization of α,α-dihalocarbonyl compounds as synthetic equivalents to α-halocarbonyl compounds has been explored in the synthesis of a wide range of highly useful heterocycles and α- functionalized ketones. The continuously growing demand of α,α-dibromoketones, as highly reactive and mild synthetic precursors/intermediates, to carry out selective organic transformations, prompted us to investigate their potential application for the synthesis of thiazolo[3,2-a]benzimidazoles. In this study, a remarkable application of α,α-dibromoacetophenones 5a-g in the development of a facile protocol for the synthesis of thiazolo[3,2-a]benzimidazoles 4a-g by avoiding the use of lachrymatory α- haloketones is described. Although the mechanism for the debromination from the intermediate compound 6 under these conditions is not confirmed, possible pathways have been suggested.

Keywords: α, α-Dibromoacetophenones, condensation, debromination, polyphosphoric acid (PPA), fused heterocycle, thiazolobenzimidazoles.

Graphical Abstract
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