Angewandte Chemie International Edition
© WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Picture (Angew. Chem. Int. Ed. Engl. 17/1995)
The cover picture shows a schematic representation of the arrangement in a crystal that resembles a tartan. It is the expected structure for the 1:1 adduct formed between a tetracationic cyclophane and ferrocene (green). The cyclophane was designed to permit recognition both in an external and internal fashion. Indeed, the cyclophane forms sheets and channels in the solid state through external recognition between its constituent components. The cyclophane also complexes substrates such as ferrocene within its cavity as predicted, whilst retaining the ability to form highly structured three-dimensional arrays, in common with the free cyclophane. Stoddart et al. use 1,4-bis(2-bromoethoxy)benzene (red) and bipyridine (blue) as building blocks to assemble the desired tetracationic cyclophane. More about the free cyclophane and its 1:1 ferrocene adduct—examples of “molecular mosaics”—are reported on p. 1862 ff.