Related Experiment Video
Updated: May 21, 2026

Synthesis of a Water-soluble Metal–Organic Complex Array
Published on: October 8, 2016
Tris(cis-2-hy-droxy-cyclo-hexane-1,3,5-tri-aminium) hydrogen sulfate octa-chloride dihydrate
Christian Neis1, Günter J Merten, Kaspar Hegetschweiler
1Fachrichtung Chemie, Universität des Saarlandes, Postfach 151150, D-66041 Saarbrücken, Germany.
Abstract:
The 2-hy-droxy-cyclo-hexane-1,3,5-triaminium (= H(3)L(3+)) cation of the title compound, 3C(6)H(18)N(3)O(3+)·8Cl(-)·HSO(4) (-)·2H(2)O, exhibits a cyclo-hexane chair with three equatorial ammonium groups and one axial hy-droxy group in an all-cis configuration. The hydrogen sulfate anion and two water mol-ecules lie on or in proximity to a threefold axis and are disordered. The crystal structure features N-H⋯Cl and O-H⋯Cl hydrogen bonds. Three C(3)-symmetric motifs can be identified in the structure: (i) Two chloride ions (on the C(3)-axis) together with three H(3)L(3+) cations constitute an [(H(3)L)(3)Cl(2)](7+) cage. (ii) The lipophilic C(6)H(6)-sides of three H(3)L(3+) cations, which are oriented directly towards the C(3)-axis, generate a lipophilic void. The void is filled with the disordered water mol-ecules and with the disordered part of the hydrogen sulfate ion. The hydrogen atoms of these disordered moieties were not located. (iii) Three H(3)L(3+) cations together with one HSO(4) (-) and three Cl(-) counter-ions form an [(HSO(4))(H(3)L)(3)Cl(3)](5+) cage. Looking along the C(3)-axis, these three motifs are arranged in the order (cage 1)⋯(lipophilic void)⋯(cage 2). The crystal studied was found to be a racemic twin.
Related Concept Videos
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group with both...
Naming Enantiomers
Disubstituted Cyclohexanes: cis-trans Isomerism
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
Chirality at Nitrogen, Phosphorus, and Sulfur
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
Stereoisomerism
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Stereoisomerism of Cyclic Compounds

