Linear pi-acceptor-templated dynamic clipping to macrobicycles and [2]rotaxanes.

Cage me! A linear dumbbell-shaped bipyridinium molecule can template cage formation around itself through sixfold imine bond formation to give an interlocked [2]rotaxane as the single product (see picture). This highly efficient [2+3] clipping occurs despite the symmetry mismatch between the template and the formed macrobicycle.