Related Experiment Video
Updated: Jun 8, 2026

Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
The first square-planar copper(II) 1:2 complex with differently coordinated 2-hydroxybenzaldehyde
1Institute of General and Inorganic Chemistry, National Academy of Science of Ukraine, Prospekt Palladina 32/34, Kyiv 03680, Ukraine. bon@ionc.kiev.ua
Abstract:
The title compound, [(Z)-4-allyl-2-(2-hydroxybenzylidene)thiosemicarbazide-κS][(E)-4-allyl-1-(2-oxidobenzylidene)thiosemicarbazidato-κ(3)O,N(1),S]copper(II) monohydrate, [Cu(C(11)H(11)N(3)OS)(C(11)H(13)N(3)OS)]·H(2)O, crystallized as a rotational twin in the monoclinic crystal system (space group Cc) with two formula unit (Z' = 2) in the asymmetric unit, one of which contains an allyl substituent disordered over two positions. The Cu(II) atom exhibits a distorted square-planar geometry involving two differently coordinated thiosemicarbazone ligands. One ligand is bonded to the Cu(II) atom in a tridentate manner via the phenolate O, azomethine N and thioamide S atoms, while the other coordinates in a monodentate manner via the S atom only. The complex is stabilized by an intramolecular hydrogen bond, which creates a six-membered pseudo-chelate metalla-ring. The structure analysis indicates the presence of the E isomer for the tridentate ligand and the Z isomer for the monodentate ligand. The crystal structure contains a three-dimensional network built from intermolecular O-H...O, N-H...O, O-H...N and N-H...S hydrogen bonds.
More Related Videos
09:35Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
Related Concept Videos
Coordination Number and Geometry
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...
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...
Valence Bond Theory
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
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...