Cu I Assembled Rotaxanes

Two equivalents of acetylenic stopper 52, [Cu(CH3CN)4](PFg) as catalyst (0.5 eq.) and Na2C03 as a base (0.4 eq.) were added. The progress of the reactions was followed by TLC analysis, which clearly showed the consumption of compound 53. Nevertheless, supplementary additions of copper(I) (0.25 eq.), stopper 52 (1 eq.), and Na2C03 and stirring overnight were necessary for the reaction to be complete. 

Using iron(II) as a template instead of copper(I), and a non-sterically hindering macrocycle 58, led to an original [3]rotaxane This novel gathering-and-double- 

Once again, the use of azide precursors and their subsequent threading and transformation to 1,2,3-triazole rings provided an easy and high-yield access to new interlocked molecules, and more complicated systems synthesized by this procedure have also recently been reported soon. 

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