Organoclay Derivatives in the Synthesis of Macrocycles.

As an alternative to the rotaxane method, an organoclay can be used as a template for the efficient formation of macrocycles (ring in schematic representation) which are easily extracted from the clay interlayer space. The four-step synthesis involved preparation of a pillared clay from the dihydrochloride salt of p-xylylenediamine, insertion of neutral p-xylylenediamine into the pillared structure, reaction of the neutral p-xylylenediamine in the layers with isophthaloyl chloride and formation of the tetramide macrocycle, and extraction of the product from the clay.