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Updated: Aug 11, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Asymmetric synthesis of 2H-azirines derived from phosphine oxides using solid-supported amines. Ring opening of
Francisco Palacios1, Domitila Aparicio, Ana María Ochoa De Retana
1Departamento de Química Orgánica I, Facultad de Farmacia, Universidad del País Vasco, Apartado 450, 01080 Vitoria, Spain. qoppagaf@vf.ehu.es
Abstract:
A simple and efficient asymmetric synthesis of 2H-azirine-2-phosphine oxides 3 is described. The key step is a solid-phase bound achiral or chiral amine-mediated Neber reaction of beta-ketoxime tosylates derived from phosphine oxides 1. Reaction of 2H-azirines 3 and 11 with carboxylic acids 4 gives phosphorylated ketamides 5 and 12. Ring closure of ketamides 5 and 12 with triphenylphosphine and hexachloroethane in the presence of triethylamine leads to the formation of phosphorylated oxazoles 8 and 13.
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