Synthesis of azomethine macrocycles by condensation of dicarbonyl compounds with diamines without using metal ions as template agents

Different strategies for the synthesis of symmetrical and unsymmetrical macrocyclic Schiff bases in the absence of metal ions are considered. General methods for performing macrocyclisation under thermodynamic or kinetic control are analysed. The key factors influencing the structure of macrocyclic azomethines are discussed.