Related Experiment Video
Updated: Apr 2, 2026
Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Nickel(II) complex derived from 5-phenyl-1,3,4-oxadiazole-2-thiol and dppe ligands: synthesis, crystal structure,
Beriwan Muhamad Hamad Ameen1, Karwan Omer Ali2, Rezan Ali Saleh1
1Department of Chemistry, College of Education, Salahaddin University-Erbil, Erbil 44001, Iraq.
Abstract:
In this study, the novel Ni(II) complex [Ni(N-L)(S-L)(dppe)], where L = 5-phenyl-1,3,4-oxadiazole-2-thiol (HL), was synthesised. The Ni(II) complex was characterised by FT-IR and UV-Vis spectroscopy, molar conductivity, and single-crystal X-ray diffraction. The complex crystallises in a monoclinic system (P21/c) with a distorted square-planar geometry. One HL ligand coordinates with the Ni(II) ion through sulphur in its thiol form, while the other HL ligand is ligated via the nitrogen atom in the thione form. The dppe ligand chelates Ni(II) via two phosphorus atoms forming a five-membered ring. The complex exhibits strong cytotoxicity against MCF7 (IC50 = 6.76 µg/mL) and A549 (IC50 = 8.07 µg/mL) cell lines. DFT results indicate that the synthesised nickel(II) complex is less thermodynamically stable than the free ligands, with a ΔE value of 3.4349 eV. Hirshfeld surface analysis was conducted to identify intermolecular interactions as the key contributors to crystal packing.
Related Concept Videos
02:46Crystal 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,...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
01:22EDTA: Chemistry and Properties
02:57Coordination Number and Geometry
02:42Valence Bond Theory
02:34Structural 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...