title: meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane as a building block in supramolecular chemistry; salts formed with 2,2-biphenol, 4,4-thiodiphenol, 4,4-sulfonyldiphenol, 3-and 4-hydroxybenzoic acids, 3,5-dihydroxybenzoic acid and phenylphosphonic acid; supramolecular structures in zero, one, two and three dimensions
abstract: The structure of meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-2,2'-biphenol (1/2), (C16H36N4).(C12H10O2)2 (1), is a salt [C16H38N4]2+.2[HOC6H4C6H4O]-: the cations are centrosymmetric with two protons held within the N4 cavity of the macrocycle by N-H...N hydrogen bonds, and the phenolate anions contain intramolecular O-H...O-hydrogen bonds. The ions are linked into a finite centrosymmetric aggregate by means of N-H...O hydrogen bonds. meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane-4,4'-thiobiphenol-methanol (1/2/2), (C16H36N4).(C12H10O2S)2.(CH4O)2 (2), and meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-4,4'-sulfonylbiphenol-methanol (1/2/2), (C16H36N4).(C12H10O4S)2.(CH4O)2 (3), are isomorphous: each is a salt, [C16H38N4]2+.2[HOC6H4SC6H4O]-.2MeOH (2) and [C16H38N4]2+.2[HOC6H4SO2C6H4O]-.2MeOH (3), and in each the phenolate anions are linked by O-H...O- hydrogen bonds into chains; antiparallel pairs of chains are cross-linked by the cations to form molecular ladders, with neutral methanol molecules acting as spacer units. In meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-3-hydroxybenzoic acid-methanol (1/2/2) (4), 3-hydroxybenzoate anions form chains, again cross-linked in pairs by the [C16H38N4]2+ cations to form molecular ladders, different from those in (2) and (3) in that the neutral methanol units are pendent from the ladders, rather than forming a part of it. meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane-4-hydroxybenzoic acid-methanol (1/2/1) (5) is again a salt, [C16H38N4]2+.2[HOC6H4COO]-.MeOH: chains of 4-hydroxybenzoate anions are continuously cross-linked by two different types of [C16H38N4]2+ cation into a two-dimensional net. Only one of the two types of cation is linked to the chains via neutral methanol spacer units. meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane-phenylphosphonic acid-water (1/4/2) (6) is a salt, [C16H40N4]4+.4[C6H5PO3H]-.2H2O, containing the centrosymmetric tetraprotonated amine units, which have a conformation quite different from the trans-III conformation uniformly found in the [C16H38N4]2+ cations. The phenylphosphonate anions and the water molecules are linked into chains of fused rings, which are linked by the cations into two-dimensional nets. In meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetrade cane-3,5-dihydroxybenzoic acid (1/2) (7), the 3,5-dihydroxybenzoate anions in the unsolvated salt [C16H38N4]2+.2[(HO)2C6H3COO]- are linked into continuous two-dimensional nets, which are in turn linked by the centrosymmetric cations to form a three-dimensional framework. meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclo tetradecane-4,4'-biphenol (1/3) (8) is a salt containing both neutral and anionic biphenol units, [C16H38N4]2+.2[HOC6H4-C6H4O]-.[HOC6H4C6H4OH]. The two types of biphenol unit form two-dimensional nets and these nets are linked by the cations to form three independent, three-dimensional frameworks which are fully interwoven, but not bonded to one another.
authors.affiliation: School of Chemistry, University of St Andrews, Fife, Scotland.
authors.initials: RM
authors.lastname: Gregson
authors.initials: C
authors.lastname: Glidewell
authors.initials: G
authors.lastname: Ferguson
authors.initials: AJ
authors.lastname: Lough