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Updated: Jul 15, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Rich pseudopolymorphic behavior of the tetranuclear [Ni4(dpyatriz)2(NO3)8] complex
Hélène Casellas1, Olivier Roubeau, Simon J Teat
1Leiden Institute of Chemistry, PO Box 9502, 2300 RA Leiden, The Netherlands.
Inorganic Chemistry
|April 19, 2007
Summary
A new tetranuclear nickel coordination compound was synthesized and characterized. This study reveals unique anion-pi interactions and the formation of multiple pseudopolymorphic phases in nickel-organic frameworks.
Area of Science:
- Coordination Chemistry
- Materials Science
- Crystallography
Background:
- The dpyatriz ligand, 2,4,6-tris(bis(pyridin-2-yl)amino)-1,3,5-triazine, is a versatile building block for metal-organic frameworks.
- Nickel(II) coordination compounds are of interest due to their diverse magnetic and catalytic properties.
Purpose of the Study:
- To synthesize and characterize a novel tetranuclear nickel(II) coordination compound with the dpyatriz ligand.
- To investigate the solid-state structure, including anion-pi interactions and pseudopolymorphism.
- To explore the interconversion between different pseudopolymorphic phases.
Main Methods:
- Single-crystal X-ray diffraction using synchrotron radiation.
- Powder X-ray diffraction (PXRD).
- Spectroscopic techniques (IR, UV-Vis), elemental analysis, thermogravimetric analysis (TGA), and magnetic susceptibility measurements.
Main Results:
- Synthesis and crystal structure determination of the tetranuclear nickel(II) compound [Ni4(dpyatriz)2(NO3)8(CH3CN)2(H2O)2].2CH3CN.
- Observation of significant anion-pi interactions between nitrate anions and triazine rings.
- Identification and characterization of several pseudopolymorphic phases (2-5) arising from hydration/solvation variations.
- Determination of the phase interconversion scheme under controlled heating.
- Assessment of structural features of pseudopolymorphs using ab initio powder diffraction.
Conclusions:
- The synthesized nickel(II) coordination compound exhibits interesting structural features, including anion-pi interactions.
- The [Ni4(dpyatriz)2] core can form multiple pseudopolymorphic phases, demonstrating the dynamic nature of solvated coordination compounds.
- Understanding these phase transitions is crucial for controlling the properties of metal-organic materials.
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