The template-directed synthesis of porphyrin-stoppered [2]rotaxanes

Abstract

Two [2]rotaxanes, composed of (i) a polyether chain intercepted by (a) one centrally-located and (b) two symmetrically-located π-electron-rich hydroquinol rings and terminated by free-base and metallated (Zn) tetraaryl-porphyrin groups respectively and (ii) a tetracationic cyclophane constructed of two π-electron-deficient bipyridinium units linked by paraphenylenedimethyl residues, have been self-assembled by a clipping procedure.