Fig. 1: Synthesis of [n]cycloparaphenylenes ([n]CPPs) with multiple functional groups.

a [n]CPPs (n ≥ 8) with substituents at all aromatic rings10,11,12,13. b Partially substituted [n]CPPs (n ≤ 6) with a small ring size14,15. c [6]Cycloparaphenylene derivatives consisting of hydroquinone ether units with 2,5-dimethoxy groups at all benzene rings, produced from macrocyclic Au complex (Cy = cyclohexyl) (This work)16. The red-colored bonds represent the bonds formed in the reaction.