Translational Isomerism in a [3]Catenane and a [3]Rotaxane

Post-assembly covalent modification using Wittig chemistry of [2]rotaxane ylides, wherein NH₂⁺ centers in the dumbbell-shaped components are recognized by dibenzo[24]crown-8 (DB24C8) rings, has afforded a [3]catenane and a [3]rotaxane with a precise and synthetically prescribed shortage of DB24C8 rings. The nondegenerate pairs of translational isomers present in both of these interlocked molecular compounds provide the fundamental platform on which to construct sensory devices and nanochemomechanical systems.