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Updated: Nov 9, 2025
Author Spotlight: A Rapid, Microwave-Assisted Hydrothermal Synthesis Of Nickel Hydroxide Nanosheets
Published on: August 18, 2023
Nickel(II) Complex with a Flexidentate Ligand Derived from Acetohydrazide: Synthesis, Structural Characterization and
Abstract:
The mononuclear Ni(II) complex [Ni(Lp)2(CH3OH)2]Cl2 has been synthesized by reacting 1-(5-hydroxy-3-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl)ethan-1-one ligand (HL) with NiCl2·6H2O in methanol solution. In the reaction, the tridentate ligand, HL, was converted in situ into 4-hydroxy-4-phenylbut-3-en-2-ylidene)acetohydrazid ligand, (pyrazole, Lp). The pyrazole ligand acts as bidentate neutral ligand and the hydroxyl group is left uncoordinated. The structure of the Ni(II) complex has been established by X-ray crystallography. The Ni(II) is six-coordinate and has a distorted octahedral geometry. It is bonded by two nitrogen and by two oxygen atoms of the two pyrazole ligands and two oxygen atoms of methanol molecules. The Hirshfeld surface analysis and the 2D the fingerprint plot are used to analyses all of the intermolecular contacts in the crystal structures. The main intermolecular contacts are H/H and Cl/H interactions.
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