Metal-free methods in the synthesis of macrocyclic Schiff bases

An overview describing an approach toward the design and optimization of symmetrical and unsymmetrical macrocyclic Schiff base is presented. The data dealing with the synthesis of macrocyclic azomethines are collected and analyzed under metal-free conditions and it is found that anions of appropriate size and geometry act as template agents in the synthesis of macrocylces containing pyrrole fragments.