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Ni[(EPiPr2)2N]2 complexes: stereoisomers (E = Se) and square-planar coordination (E = Te)
Nikolaos Levesanos1, Stuart D Robertson, Dimitrios Maganas
1Inorganic Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, GR-157 71 Athens, Greece.
Inorganic Chemistry
|March 19, 2008
Summary
Researchers synthesized novel nickel complexes, Ni[(SeP(iPr)2)2N]2 and Ni[(TeP(iPr)2)2N]2, with varying stereoisomers (square-planar and tetrahedral) influenced by solvent choice.
Area of Science:
- Organometallic chemistry
- Coordination chemistry
- Main group chemistry
Background:
- The synthesis of novel metal complexes with unique structural and stereochemical properties is a key area in inorganic chemistry.
- Exploring the reactivity of phosphorus-chalcogen ligands with transition metals can lead to new coordination compounds.
Purpose of the Study:
- To synthesize and characterize novel nickel complexes using phosphorus-chalcogen ligands.
- To investigate the stereoisomerism of the resulting nickel complexes, specifically square-planar and tetrahedral forms.
- To explore the influence of recrystallization solvents on the stereochemical outcome.
Main Methods:
- Reaction of bis(dialkylphosphino)amide precursors (Li/Na) with NiBr2·DME in tetrahydrofuran (THF).
- Isolation and purification of nickel complexes via recrystallization.
- Characterization of the synthesized complexes, including stereoisomer determination (e.g., square-planar and tetrahedral).
Main Results:
- The selenium analogue, Ni[(SeP(iPr)2)2N]2, was successfully synthesized and isolated as both green (square-planar) and red (tetrahedral) stereoisomers, dependent on the recrystallization solvent.
- The tellurium analogue, Ni[(TeP(iPr)2)2N]2, was obtained exclusively as the square-planar complex.
Conclusions:
- The study demonstrates the successful synthesis of novel nickel complexes incorporating phosphorus-chalcogen ligands.
- Recrystallization solvent plays a critical role in determining the stereochemistry (square-planar vs. tetrahedral) of the Ni[(SeP(iPr)2)2N]2 complex.
- The tellurium analogue exhibits a preference for the square-planar geometry under the studied conditions.
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