ABSTRACT A general view of the von Braun degradation of the amides, its special appliance to the preparation of N-(ω-haloalkyl)amides and our own experimental results in this subject are presented. For this purpose, a series of N-acylpirrolidines and piperidines were treated with different reagents in various conditions. Phosphorous pentachloride, thionyl and oxalyl chlorides were employed, in the presence of solvent (o-xylene, cyclohexane) and in neat conditions. Among tested reagents, phosphorous pentachloride proved to be the best. Although cyclohexane was appropriate solvent in some cases, in general the best results were obtained in solvent free reactions. The limitation of the method appears to be the presence of α-hydrogen in the acyl moiety.
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