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RESEARCH ARTICLE (Open Access)

A concise one-pot synthesis of flavones by cyclisation of o-(alkynon-1-yl)phenols

Khalid Widyan https://orcid.org/0000-0002-6483-8334 A *
+ Author Affiliations
- Author Affiliations

A Department of Chemistry and Chemical Technology, Tafila Technical University, PO Box 179, Tafila, Jordan.

* Correspondence to: k.widyan@ttu.edu.jo

Handling Editor: Jenny Pringle

Australian Journal of Chemistry 78, CH25044 https://doi.org/10.1071/CH25044
Submitted: 4 April 2025  Accepted: 15 September 2025  Published online: 6 October 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

A concise one-pot process for producing flavones and 2-alkyl-4H-benzopyran-4-one from a variety of salicylic acylbenzotriazoles is described. The in situ generation of o-(alkynon-1-yl)phenols in the ionic liquid 1-butyl-3-methylimidazoliumtetrafluoroborate ([BMIM][BF4]) is also described in this work. Three rounds of usage of the ionic liquid are possible without a noticeable decrease in efficiency.

Keywords: benzopyranone, flavones, green chemistry, ionic liquid, ionic liquid recycling, N-(o-hydroxyarylacyl)benzotriazoles, o-(alkynon-1-yl)phenols, one-pot synthesis.

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