The Formation of 2-Isoxazolines in the Reactions of α,β-Unsaturated Carbonyl Compounds with Hydroxylamine and its Derivatives-A Critical Review

Background: For more than one hundred years, it has been known that some 2- isoxazolines can be experimentally obtained by the addition of hydroxylamine or its derivatives to α,β-unsaturated carbonyl compounds. Methodology: General methods for the formation of 2-isoxazolines have not been formulated yet. Conclusion: This review will attempt to summarize the numerous published experimental facts on the addition of hydroxylamine or its derivatives to unsaturated carbonyl compounds and analyze these facts in the hope of proposing reaction pathways compatible with the all the experimental data. Keywords: Enal, enone, hydroxylamine, isoxazole, isoxazoline, isoxazolidine, oxime.