Cover Picture (Angew. Chem. Int. Ed. Engl. 10/1989)


original image

The cover picture shows a computer-generated space-filling model (D. Williams) of the structure of a highly ordered [2] catenane. This compound could be prepared in a one-pot synthesis in a yield of 70% (for comparison, use of the high-dilution technique generally affords yields of around 1%). The initially formed decaoxa[13.13]paracyclophane (drawn in red) acts as a template for generation of cyclobis(paraquat-p-phenylene) (drawn in blue) in such a way that, after cyclization, the two ring systems are interlocked. This synthetic principle, involving the exploitation of supramolecular structures, should prove to be very useful. Further details on this [2]catenane, its molecular structure, its dynamic behavior in solution, and its electrochemical properties are reported by J. F. Stoddart et al. on page 1396.