Reversible Mechanical Switching of Magnetic Interactions in a Molecular Shuttle

We developed an acid–base switchable molecular shuttle based on a [2]rotaxane, incorporating stable radical units in both the ring and dumbbell components. The interaction between the radicals can be reversibly switched from uncoupled (upon acid addition) to coupled (upon base addition). Hence, this molecular machine is capable of switching on/off magnetic interactions by chemically driven reversible mechanical effects