Synthesis of a Tetracorannulene-perylenediimide That Acts as a Selective Receptor for C-60 over C-70

We report the use of a tetraborylated perylenediimide as starting material for the preparation of a tetracorannulene-perylenediimide that is able to bind up to two fullerene-C-60 molecules by host-guest molecular recognition with preference over C-70. Titration with fullerene-C-60 is followed by a dramatic shift of the aromatic signals in H-1 NMR and an initial increase in the fluorescence of the system. By this simple mechanism, fluorogenic sensing of fullerene-C-60 is easily accomplished by an unprecedented fluorescent turn-on mechanism.