Synthesis of Bis(N-acylamidines) from Amidines and N-Acylbenzotriazoles

Abstract

Bis(N-acylamidines) 7, linked by a spacer connected to the carboxyl groups, were synthesized in moderate to good yields from bis(N-acylbenzotriazoles) 6 and amidines 2. In contrast, the corresponding bis(carboxylic acid) chlorides were not well suited for the synthesis of the compounds 7. 2-Aminothiazole gave the bisamide 8, where the amidine moieties are part of heterocyclic ring systems. Furthermore, the reaction of a bis-amidine 9 with two equivalents of N-benzoylbenzotriazole (10) gave the bifunctional N-acylamidine 11, linked to the spacer at the amidine carbon atoms. All substances were thoroughly characterized including nine X-ray diffraction studies.