Fluorinative Beckmann fragmentation: fluorinative alpha-cleavage of cyclic ketoximes by diethylaminosulfur trifluoride.

Diethylaminosulfur trifluoride reacted with cyclic ketoximes bearing substituent(s) that can stabilize a carbocation to cause fluorinative fragmentation, affording fluorinated carbonitrile. Ketoximes lacking such substituents afforded complex mixtures. However, the introduction of a sulfur functionality, which can stabilize a carbocation and can be easily removed from the reaction products, into the ketoxime was effective for producing the fluorinative fragmentation.