HOFMANN-LOEFFLER-FREYTAG Pyrrolidine Synthesis

HOFMANN - LOEFFLER FREYTAG Pyrrolidine Synthesis Synthesis of pyrrolidines or piperidines from N-haloamlnes (free radical reaction). [Pg.175]

HOFMANN Amide degradation 173 HOFMANN IsonitrHe synthesis 173 HOFMANN Elimination 174 HOFMANN LOEFFLER - FREYTaG Pyrrolidine synthesis 175... [Pg.225]

The so-called Hofmann-Loeffler-Freytag reaction" " of TV-chloroamines 9 proceeds by a similar mechanism, and is for example used for the synthesis of pyrrolidines 11 ... [Pg.27]

The synthesis of pyrrolidines by the free radical transformation of (V-chloroamines, the Hofmann-Loeffler-Freytag reaction, is of preparative significance. The key step is the formation of a radical cation which abstracts hydrogen intramolecularly to form a carbon-based radical (Scheme 21(a)). This species then abstracts chlorine from another TV-chloroamine (60JA1657, 50JA2118). The observed positional selectivity for hydrogen abstraction is a consequence of the preferred adoption of a six-membered transition state. A typical conversion achieved is indicated in Scheme 21(b). [Pg.520]

Big Chemical Encyclopedia