Macrocycles from Perhalogenated Heterocycles

Perhalogenated heteroaromatic systems, such as trichloro‐ s ‐triazine and pentafluoropyridine, are multifunctional “building blocks” that react with a number of appropriate difunctional nucleophiles to provide access to a variety of macrocyclic and even cage‐like molecular architectures. Unusual structural and complexation characteristics of the systems reported so far, such as the recognition of anions, provide a further stimulus for the development of this area.