Amidine als Zwischenprodukte bei Umamidierungsreaktionen. 9. Mitteilung über Umamidierungsreaktionen

Amidines as Intermediates in Transamidation Reactions By loss of water in the presence of p ‐toluenesulfonic acid/xylole N ‐aminoalkyllactames form bicyclic amidines. The corresponding N ‐alkylaminoalkyl‐lactames' react to bicyclic amidinium salts or to transamidated products, ring‐enlarged by the N ‐alkylamino residue, respectively (s. Scheme 1 ). The bicyclic amidines and amidinium salts are partially hydrolyzed by KOH/H 2 O to lactames (s. Scheme 2 ). Which of the two possible isomeric lactames are formed is discussed.