Ring-Strain-Driven Annulation of Cyclopropenones with Hydrazones via Nucleophilic Phosphine Catalysis
Abstract
Herein, we demonstrate a ring-strain-driven annulation of cyclopropenones with hydrazones via simple phosphine catalysis, providing an efficient route to structurally diverse 1,3,4-oxadiazolines and spiro -1,3,4-oxadiazolines under mild conditions. The reaction proceeds through the formation of a reactive α-ketenyl phosphorus ylide intermediate, generated by the interaction of cyclopropenone with a nucleophilic phosphine catalyst. Notably, an intriguing acyl group migration-mediated [3+2] annulation is observed with hydrazones derived from linear ketones, while a ring-opening addition/cyclization cascade takes place with cyclic hydrazones.
Fields of Study & Subjects
Synthesis and Reactivity of Heterocycles
Cyclopropane Reaction Mechanisms
N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
Publication details
- Journal / source
- Organic Letters
- Publisher
- American Chemical Society (ACS)
- Volume
- 28
- Issue
- 6
- Pages
- 2056–2061
- Publication date
- 29 January 2026
- Language
- EN