Macrocycles 2-6 were synthesised using a convergent synthetic pathway via a symmetrical bisazide and bis-iodoalkyne double CuAAC click macrocyclization step (Scheme 1). To synthesise the bis-azide precursors, we furnished para-bisiodobenzene derivatives with alkynes bearing terminal hydroxyl groups in a highly efficient Sonogashira reaction (for full synthetic details see §1 of the SI). This was followed by reductions of the alkyne bond, installation of methylsulfonic groups on the terminal hydroxyls and their displacement with azide moieties in the final step yielding the bis-azide. The symmetrical iodoalkynes were obtained from the corresponding alkynes and then coupled with the azides according to literature procedures. In this final ringclosing step, the formation of the [2+2] dimeric macrocycle side product was observed to compete with the formation of the desired monomeric [1+1] macrocycles. Analysis of the monomer:dimer ratio in the crude mixture for macrocycles 4 and 5 revealed a strong dependence on size and concentration. For 4, the ratio of monomer:dimer shifted from ~1:4 to ~1:1 when the concentration of macrocycle precursors was decreased from 5 mM to 0.5 mM. For the larger macrocycle 5, an increased ratio of 2:1 was obtained under the same dilute conditions. This indicated a significant strain-induced kinetic barrier in the cyclisation step, which is increased with a shorter linker, and suggested that the synthesis of macrocycles with even shorter linkers would likely not be feasible.