Remarkable Effects of Chirality on Deslipping Reactions of Diastereomeric Rotaxanes and Relevant Mechanism Involving Pre-Equilibrium

The first clear differentiation on deslipping rates affected by the difference in the diastereomeric stereocenters of rotaxanes up to 8.4 times and unexpectedly large steric kinetic isotope effect on the deslipping reaction (ca. 20%) were observed. On the basis of the kinetic parameters, steric kinetic isotope effect, and H-1 NMR spectra of the nondeuteriated and deuteriated rotaxanes, we propose a deslipping mechanism involving pre-equilibrium.