biostudies-literatureMajewski MAEuropean Research CouncilRoyal SocietyH2020 Marie Skłodowska-Curie ActionsEngineering and Physical Sciences Research Councile202302114https://www.ebi.ac.uk/biostudies/studies/S-EPMC10947019biostudies-literatureUnknown62(18)Rings of porphyrins mimic natural light-harvesting chlorophyll arrays and offer insights into electronic delocalization, providing a motivation for creating larger nanorings with closely spaced porphyrin units. Here, we demonstrate the first synthesis of a macrocycle consisting entirely of 5,15-linked porphyrins. This porphyrin octadecamer was constructed using a covalent six-armed template, made by cobalt-catalyzed cyclotrimerization of an H-shaped tolan with porphyrin trimer ends. The porphyrins around the circumference of the nanoring were linked together by intramolecular oxidative meso-meso coupling and partial β-β fusion, to give a nanoring consisting of six edge-fused zinc(II) porphyrin dimer units and six un-fused nickel(II) porphyrins. STM imaging on a gold surface confirms the size and shape of the spoked 18-porphyrin nanoring (calculated diameter: 4.7 nm).Angewandte Chemie (International ed. in English)Covalent Template-Directed Synthesis of a Spoked 18-Porphyrin Nanoring.PMC10947019839418EP/N017188/1885606Anderson HLVan Raden JMMajewski MAHart JSaywell AStawski WO'Shea JNClarke MfalseCovalent Template-Directed Synthesis of a Spoked 18-Porphyrin Nanoring.Rings of porphyrins mimic natural light-harvesting chlorophyll arrays and offer insights into electronic delocalization, providing a motivation for creating larger nanorings with closely spaced porphyrin units. Here, we demonstrate the first synthesis of a macrocycle consisting entirely of 5,15-linked porphyrins. This porphyrin octadecamer was constructed using a covalent six-armed template, made by cobalt-catalyzed cyclotrimerization of an H-shaped tolan with porphyrin trimer ends. The porphyrins around the circumference of the nanoring were linked together by intramolecular oxidative meso-meso coupling and partial β-β fusion, to give a nanoring consisting of six edge-fused zinc(II) porphyrin dimer units and six un-fused nickel(II) porphyrins. STM imaging on a gold surface confirms the size and shape of the spoked 18-porphyrin nanoring (calculated diameter: 4.7 nm).2023-01-01T00:00:00Z2023 Apr2025-05-18T12:53:49.388Z2025-05-18T12:53:49.388ZS-EPMC109470193687774510.1002/anie.202302114