| Abstract: | Cyclisation of N-(2-Phenylethyl)-2-(2-hydroxyethyl)benzamides The cyclisation of the hydroxyamides 3 according to Bischler-Napieralski proceeds in three ways depending on the substituents at the aromatic rings: The amides 3c and 3d , the phenylethylamine parts (ring A) of which are not activated, close only ring C. The amide 3b , which is activated in ring A but - with regard to nucleophilic attack - deactivated in ring D (lactone part), closes ring B, too, after ring C has been closed. Finally, with 3a activated in ring A only, Bischler-Napieralski cyclisation (formation of ring B) takes place first and intramolecular N-alkylation (formation of ring C) follows. |
