Stereoelectronically-induced allosteric binding: shape complementarity promotes positive cooperativity in fullerene/buckybowl complexes.

A novel 2 : 1 host-guest complex forms between 8- tert -butyl-6 b 2 -azapenta-benzo[ bc , ef , hi , kl , no ]corannulene (1) and C 60 with positive cooperativity ( α = 2.56) and high affinity ( K 1 × K 2 = 2.8 × 10 6 M -2 ) at 25 °C. The C 60 undergoes increasing shape complementarity toward 1 throughout the binding process.