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DOI: 10.1055/sos-SD-040-00445

Sweeney, J. B.Science of Synthesis, (200940683.

Other than simple (usually symmetrical) aziridines, azirines are most often precursors to polycyclic aziridines in which the nitrogen atom is located at a ring junction; the azirine acts as a heterodienophile in cycloaddition reactions, though the C=N bond is sometimes rather unreactive in these processes. 2-Aryl-2H-azirine-3-carboxylates (e.g., 127) react with 2,3-dimethylbuta-1,3-diene to give bicyclo[4.1.0]heptenecarboxylates (e.g., 152, Scheme 86), but the diene must be present in large excess.[‌231‌] In the case of chiral enantiomerically pure (2-aryl-2H-azirin-3-yl)phosphonates (e.g., 153), DielsAlder reactions are slow when simple dienes are used; as might be expected given the intimate juxtaposition with preexisting chirality, the reactions are diastereoselective.[‌232‌] (2-Oxooxazolidinyl)dienes, such as 154, undergo cycloaddition with 2H-azirines, without the need for a large excess of the diene. Chiral oxazolidinone substituents do not induce diastereoselective reaction.[‌233‌]

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