Stereoselective synthesis of an MGI catenane. Having established that a polarised NH unit appears sufficient to control the synthesis of MGI-1 rotaxanes with macrocycle 2, we briefly investigated whether the same approach could be applied to the related isomers of catenanes. Pre-macrocycle 13, which contains an activated amide unit analogous to that of 12, reacted with 2 under our AT-CuAAC catenaneforming conditions (Scheme 4) 27 to give 14 with good stereocontrol (80% de, entry 1). The same reaction in CHCl3-EtOH gave reduced the selectivity (60% de, entry 2) whereas performing the reaction at 0 °C in CH2Cl2 increased the selectivity (92% de, entry 3). Lowering the temperature further (-40 °C) had no significant effect (90% de, entry 4). Thus, unsurprisingly given the similarity of their stereogenic units, MGI-1 rotaxanes and MGI catenanes can be made with good stereocontrol using equivalent strategies. Scheme 4. Stereoselective synthesis of catenane 14. a a Reagents and conditions: 13 (2 equiv.) was added over the time stated using a syringe pump to 2 (1 equiv.), [Cu(MeCN)4]PF6 (0.97 equiv.), i Pr2EtN (4 equiv.).