showed that a small solvent such as 1,2-dichloroethane could serve as a suitable template for the small pillar [5]arene macrocycle (i = 5, yield = ite = 71%) while the larger solvent chlorocyclohexane templates the formation of the large pillar [6]arene macrocycle (i = 6, yield = ite = 87%). The oligomerization was shown to be reversible in presence of Lewis or Brønsted acids. Therefore, the iteroselectivity is under thermodynamic control. This templating strategy was successfully used to prepare larger macrocycles with reversible reactions (e.g. imine-based macrocycles) or irreversible reactions (e.g. porphyrin nanorings). Irreversible reactions, however, tend to lead to lower iteroselectivity due to the occasional formation of any smaller macrocycle or larger oligomer than the templated product.