Extraordinary Aggregation of Inorganic Anions in Chiral Metallosupramolecular Ionic Crystals

• Published in: Bulletin of the Chemical Society of Japan 2013-08, Vol.86 (8), p.908-920
• Main Authors: Lee, Raeeun, Igashira-Kamiyama, Asako, Okumura, Mitsutaka, Konno, Takumi
• Format: Article
• Language: English
• ISSN: 0009-2673; 1348-0634
• DOI: 10.1246/bcsj.20130084

An optically active AuI4CoIII2 complex with mixed D-penicillaminate (D-pen) and 1,2-bis(diphenylphosphino)ethane (dppe), [Au4Co2(dppe)2(D-pen)4]2+, was selectively formed from [Au2(dppe)(D-pen)2]2− and CoIII. When this complex was crystallized with monovalent anions (ClO4−, BF4−, NO3−, Cl−, Br−, and N3−), the AuI4CoIII2 complex cations were self-assembled to form +12-charged supramolecular octahedrons that are closely packed in a face-centered cubic (fcc) structure. In this structure, ten monovalent anions are accommodated in each hydrophilic tetrahedral interstice to create an adamantane-shaped anionic cluster, while two anions are each encapsulated in each octahedral interstice and in the center of each supramolecular octahedron. The use of divalent anions (SO42− and SiF62−) also produced an analogous fcc structure made up of the +12-charged supramolecular octahedrons. In this case, six divalent anions are accommodated in each hydrophilic tetrahedral interstice to form an octahedron-shaped anionic cluster, completing a giant zinc blende lattice structure where all cations and anions are separately aggregated into the +12-charged octahedrons and the −12-charged octahedrons, respectively. The site selective aggregation of two kinds of inorganic anions (PF6−/Br−, BF4−/Br−, and NO3−/Br−) in the fcc structure, along with the synthesis and characterization of an analogous AuI4CrIII2 complex, is also reported.