Figure 3.

a) Chemical-shift perturbation of proton γ upon addition of Cl⁻ (⧫), AcO⁻ (▪) and H₂PO₄⁻ (▴) (as the TBA salt) to a solution of [2] rotaxane 1 (unfilled), 2 (half-filled) and 3 (filled) in 7:3 [D₆]acetone/D₂O at 293 K. b) Chemical-shift perturbation of proton c upon addition of Cl⁻ (as the TBA salt) to a solution of macrocycle 4 in 7:3 [D₆]acetone/D₂O (◊) and in 9:1 [D₆]acetone/D₂O (⧫) at 293 K. Symbols represent experimental data; continuous lines represent calculated curves.