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(18-Crown-6-κO)(pyrazolato-κN,N')-potassium(I).
Kerstin Kunz1, Hans-Wolfram Lerner, Michael Bolte
1Institut für Anorganische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt/Main, Germany.
Summary
This study details the crystal structure of a potassium compound featuring a crown ether and a pyrazolate anion. The potassium ion coordinates with oxygen atoms from the crown ether and nitrogen atoms from the pyrazolate.
Area of Science:
- Inorganic Chemistry
- Crystallography
- Coordination Chemistry
Background:
- Potassium complexes with crown ethers and heterocyclic anions are relevant in coordination chemistry.
- Understanding the coordination environment of potassium ions is crucial for designing new materials.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, [K(pyrazolate)(crown ether)].
- To analyze the coordination geometry and bonding interactions of the potassium cation.
Main Methods:
- Single-crystal X-ray diffraction was used to determine the molecular and crystal structure.
- Analysis of bond distances (K-O, K-N) and angles was performed.
Main Results:
- The asymmetric unit contains a potassium cation coordinated to six oxygen atoms of a crown ether and two nitrogen atoms of a pyrazolate anion.
- Potassium-oxygen bond distances range from 2.8416(8) to 3.0025(8) Å.
- Potassium-nitrogen bond distances are 2.7441(11) and 2.7654(11) Å, with the potassium displaced from the crown ether's oxygen plane.
Conclusions:
- The potassium cation exhibits a distorted coordination sphere due to the differing donor atoms (O vs. N).
- The relative orientation of the crown ether and pyrazolate ligands influences the overall structure.
- This structural information provides insights into the coordination behavior of potassium in complexes with mixed donor ligands.
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