Preparation of new 2,4-disubstituted oxazoles from N-acylaziridines

Abstract

The efficiency of the ring enlargement of 2-substituted N-acylaziridines to dihydrooxazoles followed by nickel peroxide oxidation to give 2,4-disubstituted oxazoles as a synthetic route is examined. Sodium iodide-promoted ring enlargements work well for N-acylaziridines bearing electron-donating 2-substituents. For N-acylaziridines bearing electron-withdrawing 2-substituents, the best results are obtained using acid-promoted rearrangement.

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