EQUILIBRIUM-CONSTANT FOR THE CATENATION OF 2 HARD TORI

The equilibrium constant and Gibbs energy for the catenation reaction of two hard tori were calculated at several values of the ratio of min or radius to major radius gamma = r(t)/R(t). The results were used to 1) estimate the fraction of catenated molecules formed in a 'statistic al' synthesis, and 2) estimate the theoretical maximum increase in com plexing ability obtained by catenation of two complexing ligands. The catenated complexing ligands synthesized by Dietrich-Buchecker et al. do not realize the theoretical enhancement due to confinement of the r ing motions in the metal complex. Theoretical arguments show that, in the case of ideal gas and colligative properties, the catenated molecu le must be considered as one molecule even though it is only held toge ther by topological bonds.