Molecular Borromean Rings

• Published in: Science (American Association for the Advancement of Science) Vol. 304; no. 5675; pp. 1308 - 1312
• Main Authors: Chichak, Kelly S., Cantrill, Stuart J., Pease, Anthony R., Chiu, Sheng-Hsien, Gareth W. V. Cave, Atwood, Jerry L., Stoddart, J. Fraser
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 28.05.2004; The American Association for the Advancement of Science
• Subjects: Anions; Atoms; Chemical reactions; Chemistry; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with n hetero atom and also o and/or s, se, te hetero atoms; Ions; Knot theory; Ligands; Mathematical rings; Molecular structure; Molecules; NMR; Nuclear magnetic resonance; Organic chemistry; Preparations and properties; Protons; Self assembly; Spectrum analysis; Topology; United States; Molecular assembly; Supramolecular structure; Catenane; Transition metal Complexes; Zinc Complexes; Oxygen nitrogen heterocycle; Macrocycle; Pyridine derivatives
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1096914

The realization of the Borromean link in a wholly synthetic molecular form is reported. The self-assembly of this link, which is topologically achiral, from 18 components by the template-directed formation of 12 imine and 30 dative bonds, associated with the coordination of three interlocked macrocycles, each tetranucleating and decadentate overall, to a total of six zinc(II) ions, is near quantitative. Three macrocycles present diagonally in pairs, six exo-bidentate bipyridyl and six endo-diiminopyridyl ligands to the six zinc(II) ions. The use, in concert, of coordination, supramolecular, and dynamic covalent chemistry allowed the highly efficient construction, by multiple cooperative self-assembly processes, of a nanoscale dodecacation with an approximate diameter of 2.5 nanometers and an inner chamber of volume$250 \AA^3$, lined with 12 oxygen atoms.