Related Experiment Video
Updated: Jun 28, 2026

Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
A noncentrosymmetric 3D coordination polymer of metallocalix[4]arene
Yu-Juan Liu1, Jie-Sheng Huang, Stephen Sin-Yin Chui
1Coordination Chemistry Institute, The State Key Laboratory of Coordination Chemistry, Nanjing University, 210093 Nanjing, P. R. China.
Abstract:
Sequential reaction of a lower-rim functionalized calix[4]arene, 25,27-bis(hydroxycarbonylmethoxy)-26,28-dimethoxy-p-tert-butylcalix[4]arene (H(2)L(C4)), with K(2)CO(3) and CoCl(2).6H(2)O in ethanol afforded a 3D coordination polymer [K(3)Co(2)(L(C4))(3)(EtOH)(6)]Cl (1). X-ray crystal analysis revealed that 1 features a noninterpenetrated (10,3)-a net structure wherein octahedral Co(2+) ions serve as the three-connecting nodes and [K(L(C4))](-) units function as the bridges between the Co(2+) ions. The calixarene ligands in 1 adopt a 1,3-alternate conformation, and there are considerable cation-pi interactions between the K(+) ion and the phenyl rings within each [K(L(C4))](-) unit.
Related Concept Videos
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Coordination Number and Geometry
Valence Bond Theory
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Coordination Compounds and Nomenclature
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...

