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Updated: Jun 1, 2026
08:46
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
Poly[[tetra-kis-(μ(2)-pyrazine N,N'-dioxide-κO:O')neodymium(III)] tris-(perchlorate)].
Benjamin G Quinn-Elmore1, James D Buchner, Keith B Beach
1Allegheny College, 520 North Main St., Meadville, PA 16335, USA.
Summary
This study details a novel three-dimensional coordination network featuring neodymium. The structure, {[Nd(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), exhibits a distorted square-anti-prismatic coordination around the neodymium cation, stabilized by pyrazine N,N-dioxide ligands and perchlorate anions.
Area of Science:
- Inorganic Chemistry
- Crystal Engineering
- Materials Science
Background:
- Lanthanide coordination networks are crucial for developing advanced materials.
- Understanding the structural nuances of these networks is key to controlling their properties.
- Pyrazine N,N'-dioxide ligands offer versatile coordination modes for metal ions.
Purpose of the Study:
- To synthesize and characterize a novel three-dimensional coordination network of neodymium.
- To elucidate the coordination environment of the neodymium cation within the network.
- To investigate the role of ligands and counter-ions in the overall network architecture.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the precise three-dimensional structure.
- Analysis of coordination geometry and symmetry elements was performed.
- Intermolecular interactions, including hydrogen bonding, were examined.
Main Results:
- A new 3D coordination network, {[Nd(C(4)H(4)N(2)O(2))(4)](ClO(4))(3)}(n), was successfully synthesized and structurally characterized.
- The neodymium(III) cation exhibits a distorted square-anti-prismatic coordination geometry, bonded to eight oxygen atoms from bridging pyrazine N,N'-dioxide ligands.
- Two distinct pyrazine N,N'-dioxide ligands and two unique perchlorate anions were identified, with perchlorate ions residing in channels and engaging in C-H⋯O hydrogen bonding.
Conclusions:
- The synthesized neodymium coordination network is isostructural with analogous lanthanide compounds.
- The intricate arrangement of ligands and anions dictates the network's dimensionality and stability.
- The observed hydrogen bonding interactions play a significant role in stabilizing the overall crystal structure.
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