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Please login to access the full content or check if you have access via Variation 1: The Photochemical Beckmann Rearrangement

DOI: 10.1055/sos-SD-021-00115

Judd, W. R.; Katz, C. E.; Aubé, J.Science of Synthesis, (200521161.

An important variation on the Beckmann rearrangement is the photochemical Beckmann rearrangement.[‌85‌] This method effects the conversion of an oxime into an amide via an oxaziridine, and is thus mechanistically unrelated to the classical Beckmann reaction. The regioselectivity of this photochemical rearrangement is governed by stereoelectronic factors related to the oxaziridine intermediate (see Section The photochemical reactions are typically nonregiospecific, and often result in a mixture of amides from unsymmetrical ketoximes, regardless of the oxime geometry. For example, rearrangement of the oxime 74 by treatment with thionyl chloride affords the lactam 75 as the sole product, whereas photolysis gives a 1:1 mixture of lactams 75 and 76 (Scheme 36).[‌76‌,‌86‌]

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