title: The hydrogen-bonded complex bis(tert-butylammonium) 2,6-dichlorophenolate 2,4-dichlorophenol-2,4-dichlorophenolate tetrahydrofuran disolvate containing a chiral R53(10) hydrogen-bonded ring as a supramolecular synthon.
abstract: A fixed hydrogen-bonding motif with a high probability of occurring when appropriate functional groups are involved is described as a `supramolecular hydrogen-bonding synthon'. The identification of these synthons may enable the prediction of accurate crystal structures. The rare chiral hydrogen-bonding motif R53(10) was observed previously in a cocrystal of 2,4,6-trichlorophenol, 2,4-dichlorophenol and dicyclohexylamine. In the title solvated salt, 2C4H12N+·C6H3Cl2O-·(C6H3Cl2O-·C6H4Cl2O)·2C4H8O, five components, namely two tert-butylammonium cations, one 2,4-dichlorophenol molecule, one 2,4-dichlorophenolate anion and one 2,6-dichlorophenolate anion, are bound by N-H...O and O-H...O hydrogen bonds to form a hydrogen-bonded ring, with the graph-set motif R53(10), which is further associated with two pendant tetrahydrofuran molecules by N-H...O hydrogen bonds. The hydrogen-bonded ring has internal symmetry, with a twofold axis running through the centre of the 2,6-dichlorophenolate anion, and is isostructural with a previous and related structure formed from 2,4-dichlorophenol, dicyclohexylamine and 2,4,6-trichlorophenol. In the title crystal, helical columns are built by the alignment and twisting of the chiral hydrogen-bonded rings, along and across the c axis, and successive pairs of rings are associated with each other through C-H...π interactions. Neighbouring helical columns are inversely related and, therefore, no chirality is sustained, in contrast to the previous case.
authors.affiliation: College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, People's Republic of China.
authors.forename: Xiao Qing
authors.initials: XQ
authors.lastname: Cai
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
authors.forename: Bei
authors.initials: B
authors.lastname: Tian
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
authors.forename: Jian Nan
authors.initials: JN
authors.lastname: Zhang
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
authors.forename: Zhi Min
authors.initials: ZM
authors.lastname: Jin
keywords: 2,4-dichlorophenol; 2,6-dichlorophenol; crystal structure; hydrogen-bonding synthon; supramolecular synthon; tert-butylamine