Fig. 3.

a Synthesis of rotaxane-branched dendrimer G₁ by a CuI-catalyzed coupling reaction of [2]rotaxane building block 2 and 1,3,5-triethynylbenzene; b schematic representation of a controllable divergent approach for the synthesis of rotaxane-branched dendrimers G₂ and G₃. Reaction conditions: (I) (a) TBAF, THF, r.t., 4 h, 92%; (b) 2, CuI, Et₂NH, r.t., 8 h, 62%; (II) (a) TBAF, THF, r.t., 4 h, 60%; (b) 2, CuI, Et₂NH, r.t., 8 h, 61%