DBUH-I3: A next-generation organocatalyst for arylidene isoxazolone synthesis

Ramesh Gawade; Santosh Shinde; Pramod Kulkarni

doi:10.2478/auoc-2026-0004

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DBUH-I3: A next-generation organocatalyst for arylidene isoxazolone synthesis

Ovidius University Annals of Chemistry

Volume 37 (2026): Issue 1 (January 2026)

By: Ramesh Gawade, Santosh Shinde and Pramod Kulkarni

Open Access

|May 2026

Abstract

A next-generation approach to arylidene isoxazolone synthesis is introduced using the versatile, sustainable 3,5,6,7,8,9-hexahydro-2H-imidazo[1,2-a]azepin-1-ium-iodine-iodide (DBUH-I₃) organocatalyst. This one-pot, three-component condensation of ethyl acetoacetate, substituted aryl aldehydes, and hydroxylamine hydrochloride under ethanol reflux yielded excellent results (up to 92%) across a diverse substrate range. DBUH-I₃ showed unparalleled catalytic efficiency and substrate versatility among screened amine–iodine–iodide complexes. The protocol offers operational simplicity, mild conditions, and rapid reaction rates, making it broadly applicable for the synthesis of isoxazolones. All products were structurally confirmed by FT-IR, ¹H NMR, and ¹³C NMR spectroscopy. Importantly, DBUH-I₃ overcomes iodine’s drawbacks, such as sublimation and moisture sensitivity, providing a stable, user-friendly alternative. Its compatibility with both electron-rich and electron-deficient substrates underscores its broad utility. This work establishes DBUH-I₃ as an eco-friendly, cost-effective catalyst that advances the synthesis of biologically relevant isoxazolone scaffolds and supports green chemistry applications..

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Articles in this issue

DOI: https://doi.org/10.2478/auoc-2026-0004 | Journal eISSN: 2286-038X | Journal ISSN: 1583-2430

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Language: English

Page range: 30 - 37

Submitted on: Jan 19, 2026

Accepted on: Apr 25, 2026

Published on: May 25, 2026

Published by: Ovidius University of Constanta

In partnership with: Paradigm Publishing Services

Publication frequency: 2 issues per year

Keywords:

DBUH-iodine-iodide complex,

isoxazolones,

multicomponent reaction

Related subjects:

Chemistry,

Chemistry, other

© 2026 Ramesh Gawade, Santosh Shinde, Pramod Kulkarni, published by Ovidius University of Constanta
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Volume 37 (2026): Issue 1 (January 2026)