Angewandte Chemie International Edition
© WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Picture (Angew. Chem. Int. Ed. Engl. 9/1987)
This cover shows hexaepoxyoctacosahydrocyclacene, a new macropolycyclic compound that can be prepared in a two step synthesis (!)—diastereoselective Diels-Alder reactions—from easily accessible starting compounds. Not only is the impressive synthesis of this polycycle of interest but, above all, its structure: The molecule has a crystallographic symmetry center, the two benzene rings are parallel and have a separation of 7.9 Å, and all eight methine H-atoms are oriented towards the center of the molecule. Furthermore, this cyclacene derivative paves the way for a variety of highly interesting macrocyclic analogues and derivatives, including e.g., polyunsaturated hydrocarbons which could exhibit novel electronic properties. Further details about this fascinating molecule are reported by J. F. Stoddart et al. on p. 892ff.