Steroids, Beckmann rearrangement synthesis

Expansions of oximes of B-ring steroid systems are much less common. Recently, during the synthesis of a 6-aza-pregnane derivative 387, the introduction of the nitrogen was made using the Beckmann rearrangement reaction (equation 156). 

Various studies have been devoted to the synthesis of amino-substituted steroids. These compounds can be prepared either from an alcohol, by displacement of a toluene-p-sulphonyl group by an amine, ° from a ketone, either by reduction of the corresponding oxime ° ° or by Beckmann rearrangement of 20-keto-oximes, ° or by catalytic reduction of a nitro-group. ° Another... 

DMF is recommended as diluent in the Ullmann synthesis of diaryls from aryl halides and as solvent for the Beckmann rearrangement of steroidal enone oximes. The Willgerodt-Kindler reaction (a carbonyl compound with a secondary amine and sulfur to give a thioamide) can be carried out in good yield at 50-60 if DMF is... 

Suginome, H., Kaji, M., and Yamada, S., Photo Induced Molecular Transformations. 87. Regiospecihc Photo Beckmann Rearrangement of Steroidal a,P Unsaturated Ketone Oximes Synthesis of Some Steroidal Enamino Lactams, J. Chem. Soc., Perkin Trans. 1, 1988, 321 326. 

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