Finally, we returned to apply our findings to the stereoselective synthesis of the enantiomers of MAC rotaxanes. In our original report we separated the diastereomers of epimeric rotaxanes 4a before removing the Boc group to generate rotaxane 15 (Scheme 5) in which the MAC stereogenic unit is the only fixed source of stereochemistry. This was necessary as the AT-CuAAC reaction only proceeded in 50% de; given that the ultimate purpose of developing methodologies to produce stereochemically complex mechanically interlocked molecules is ultimately so they can then be applied to solve chemical problems, for example in sensing 28 or catalysis, for which they must be available in high stereopurity, in our original report this was a necessary step.