Manabu Yanase

Fullerenes Enclosed in Bridged Calix[5]arenes

Host systems that bind C70 preferentially to C60 are found in the bridged calix[5]arenes 1 (X= alkyne bridge). The complexation-induced shifts of the bound fullerene guests provide valuable information on the structure and dynamics of the supramolecular complex.

Crystalline supramolecular complexes of C60 with calix[5]arenes

The structure of the crystalline supramolecular complexes of calix[5]arenes ( 1 – 3 ) with C 60 is described. The composite ratios of these complexes are 2:1 for 1 and C 60 and 1:1 for 2 and 3 with the guest. Van der Waals attractive interaction between the heavy halogen atoms on the upper rim of the host ( 1 ) is responsible for the formation of the 2:1 complex.

A self-assembling molecular container for fullerenes

Abstract Encapsulation of C 60 by a self-assembled supramolecular capsule based on a calix[5]arene urea derivative is described. Release of the entrapped fullerene from the ternary complex can be easily managed by the addition of a protic acid. Two pathways to give the supramolecular ternary complex are analyzed successfully.

Thermodynamic study on supramolecular complex formation of fullerene with calix[5]arenes in organic solvents

Abstract Thermodynamic parameters for the supramolecular complex formation of fullerene C 60 with calix[5]arene receptors are reported. The entropy change in chloroform is negative, but in toluene is positive, suggesting the tight solvation around the guest in toluene. Desolvation of the guest plays an important role in the supramolecular complex formation in toluene.