Synthesis of Azetidine Nitrones by Double Methylene Incorporation into Nitrile Oxides Using Diazomethane

Abstract

A novel method for preparing 4-membered azetidine nitrones, starting from isolable nitrile oxides, has been developed. The reaction of diazomethane with the bulky nitrile oxides proceeds via double nucleophilic incorporation of the methylene moiety to produce 4-membered cyclic nitrones in yields up to 74%. A reaction pathway involving the formation of a strained azirine N-oxide intermediate is discussed.

Keywords

Nitrile oxide - Diazomethane - Double methylene incorporation - Azetidine nitrone - Azirine N-oxide

Publikationsverlauf

Eingereicht: 20. Juli 2025

Angenommen nach Revision: 24. August 2025

Accepted Manuscript online:
24. August 2025

Artikel online veröffentlicht:
18. September 2025

• References


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