Schmidt reaction with unsymmetrical ketones

Migration of Groups in the Schmidt Reaction with Unsymmetrical Ketones... 

Of equal importance to the Beckmann rearrangement for the preparation of azepines and azepinones is the Schmidt reaction of ketones. Again, however, with unsymmetrically substituted cyclohexanones or with bicyclic ketones such as a-tetralone, two azepines are possible, a -Substituted cyclohexanones invariably yield the product of attack by azide ion at the least hindered side of the protonated ketone as exemplified in Scheme 19 (B-67MI51600). 

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