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Bis(2,3-dimethyl-butane-2,3-diamine)nickel(II) dinitrate monohydrate
Shen-Xin Li1, Li-Ke Zou, Bin Xie
1School of Chemistry & Pharmaceutical Engineering, Sichuan University of Science & Engineering, Zigong, Sichuan 643000, People's Republic of China.
Summary
This study details the crystal structure of a nickel(II) complex with 2,3-diamino-2,3-dimethyl-butane (tmen). The complex exhibits a square-planar geometry and forms 2D hydrogen-bonded arrays via nitrate anions and water molecules.
Area of Science:
- Coordination Chemistry
- Crystal Engineering
- Materials Science
Background:
- Nickel(II) complexes are widely studied for their diverse coordination geometries and magnetic properties.
- Tetradentate diamine ligands are crucial in stabilizing specific nickel geometries.
- Understanding hydrogen bonding networks is key to designing functional materials.
Purpose of the Study:
- To elucidate the crystal structure of the bis-(2,3-dimethyl-butane-2,3-diamine)nickel(II) complex.
- To investigate the role of nitrate anions and water molecules in the supramolecular assembly.
- To characterize the hydrogen bonding interactions within the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, angles, and intermolecular interactions (hydrogen bonds).
- Symmetry analysis of the nickel coordination sphere and hydrogen bonding network.
Main Results:
- The nickel(II) complex cation exhibits a nearly undistorted square-planar geometry.
- Two symmetry-related 2,3-diamino-2,3-dimethyl-butane (tmen) ligands coordinate to the central nickel atom.
- The crystal structure features infinite zigzag chains formed by nickel complex cations, nitrate anions, and water molecules, linked by N-H···O hydrogen bonds, forming 2D arrays.
Conclusions:
- The study provides a detailed structural characterization of a novel nickel(II)-tmen complex.
- The hydrogen bonding network plays a significant role in organizing the crystal structure into layered arrays.
- The findings contribute to the understanding of supramolecular chemistry and crystal engineering of metal complexes.
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