Why use Template Reactions

There are also potential disadvantages associated with the use of template methodology for the formation of macrocyclic ligands. Perhaps the most important is the observation that not all metal ions can act as templates for the specific cyclisation reactions of interest. In many cases it may not be trivial to find an appropriate template ion (if indeed 

However, it remains a fact that an enormous number of macrocyclic ligands have been, and new examples continue to be, made using template methods. 

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