Quinoline N‐Oxide: A Versatile Precursor in Organic Transformations

• Published in: ChemistrySelect (Weinheim) 2022-12, Vol.7 (48), p.n/a
• Main Authors: Singha, Koustav, Habib, Imran, Hossain, Mossaraf
• Format: Article
• Language: English
• Subjects: C−H Activation; Mechanistic Insights; Metal Catalyst; Quinoline N-Oxide; Synthetic Methods
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.202203537

Quinoline derivatives are very widely known biologically active heterocyclic compounds, as for example quinine, mefloquine, etc. In recent years, the interests of researchers are growing to look for a methodology using quinoline N‐oxides as a precursor to make several bio‐active quinoline compounds as quinoline N‐oxides are more reactive with good regioselectivity than unoxidized quinolines. In this review, numerous procedures are discussed using quinoline N‐oxides as a versatile precursor in organic transformations, such as alkenylation, alkylation, arylation, amination, amidation, halogenation and so on under metal or metal‐free conditions at C‐2, C‐3 or C‐8 positions. The main focus of this context is to explore various procedures of synthesis of quinoline derivatives with good regioselectivity, to understand the extent of usefulness of those procedures through the study of scope of substrates and the reaction mechanisms of the processes. Quinoline is regarded as an important moiety observed in various bioactive compounds. So, it is necessary to explore the routes for the synthesis of Quinoline N‐oxides. It can be considered one of the useful and potent precursors for the synthesis of derivatives of quinoline. In this review, several synthetic procedures reported in the last few years were discussed with their mechanical approaches and scope of substrates.