title: Topological classification and supramolecular chirality of 21-helical ladder-type hydrogen-bond networks composed of primary ammonium carboxylates: bundle control in 21-helical assemblies.
abstract: The supramolecular chirality of 1D ladder-type hydrogen-bond networks composed of primary ammonium carboxylates was determined based on topological considerations. Chirality in such networks is based on the absolute configuration of the primary ammonium cation, which arises from discrimination between the two oxygen atoms of the carboxylate anion. The configurations of the cations and anions generate topological diversity in the networks, which are classified into six subgroups. In the Cambridge Structural Database, salts based on ladder type 1 constitute over 70 % of salts with a 1D-ladder-type network. Ladder type 1, based on a 2(1)-axis, is not superimposable on its mirror image, which leads to the first definition of right- or left-handedness of 2(1)-helicity on the basis of supramolecular tilt chirality. Helical assemblies of 2(1)-type with triaxial chirality can be assembled in various ways to yield chiral bundles and crystals. On the basis of these considerations, we constructed clay mimic structures with several bundle patterns by connecting the hydrogen-bond networks by using bifunctional molecules. These results open up the possibility of in-depth crystal engineering based on hydrogen-bond topology.
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Tetsuharu
authors.initials: T
authors.lastname: Yuge
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Sakai
authors.forename: Nobuyasu
authors.initials: N
authors.lastname: Kai
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hisaki
authors.forename: Mikiji
authors.initials: M
authors.lastname: Miyata
authors.forename: Norimitsu
authors.initials: N
authors.lastname: Tohnai
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D046911:Macromolecular Substances / Q000737:chemistry / Q000145:classification; D008958:Models, Molecular; D015394:Molecular Structure; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D046911:Macromolecular Substances; D000644:Quaternary Ammonium Compounds