Nanosized ball joints constructed from C60 and tribenzotriquinacene sockets:: Synthesis, component self-assembly and structural investigations

The formation of supramolecular host-guest complexes of fullerene (C-60) and two novel tribenzotriquinacene based hosts (5a and 5b) was investigated in solution and in the solid state. Stability constants for 1:1 and 2:1 complexes were obtained from spectroscopic (UV/Vis, H-1 NMR) titration experiments. Association constants of K-1 = (2908 +/- 360) L mol(-1) and K-2= (2076 +/- 300) L mol(-1) for C-60/(5)a, and K-1=(5608 +/- 220)L mol(-1) and K-2= (673 +/- 160) L mol(-1) for C-60/5b were obtained. Single crystal X-ray structural analysis of compound C-60 subset of 5b.3 toluene revealed that a molecule of C-60 was located at short van der Waals contact distances in the open pre-organised cavity of the rigid host. ne supramolecular complex created resembles an engineered nanosized ball joint and represents the first member for a future nanomechanics construction kit.