Controlling Mechanical Geometrical Isomerism

Mechanical geometric isomerism, which arises when bilaterally dissymmetric components are interlocked such that their internal mirror planes can be made congruent, is under-explored using simple prochiral components. Here we demonstrate that a single intercomponent H-bond appears sufficient to control the formation of rotaxanes and catenanes containing canonical mechanical geometric stereochemistry and identify a new mechanical stereogenic unit of rotaxanes, which yielded to a shuttling auxiliary synthesis.