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Updated: Oct 4, 2025
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Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
2.9K
Strontium Hydride Cations Supported by a Large NNNNN Type Macrocycle: Synthesis, Structure, and
Thomas Höllerhage1, Thomas P Spaniol1, Ambre Carpentier2
1Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52056 Aachen, Germany.
Inorganic Chemistry
|February 9, 2022
Summary
The study isolated novel cationic strontium hydride complexes using the Me5PACP ligand. These complexes show potential in catalysis, though strontium versions exhibit lower activity than calcium analogues due to equilibrium shifts.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Catalysis
Background:
- Strontium hydride complexes are less explored than their lighter congeners.
- Macrocyclic ligands like Me5PACP (1,4,7,10,13-pentamethyl-1,4,7,10,13-pentaazacyclopentadecane) can stabilize reactive metal centers.
Purpose of the Study:
- To synthesize and characterize novel cationic strontium hydride complexes.
- To investigate the catalytic activity of these complexes in hydrogenation and hydrosilylation reactions.
Main Methods:
- Hydrogenolysis of benzyl precursors in the presence of Me5PACP.
- Isolation and characterization of strontium hydride complexes using various counterions.
- Catalytic testing of soluble dihydride complexes in olefin hydrogenation and hydrosilylation.
Main Results:
- Isolation of trihydride cation [(Me5PACP)2Sr2(μ-H)3][B(C6H3-3,5-Me2)4] and dihydride complexes [(Me5PACP)2Sr2(μ-H)2][BAr4]2.
- The soluble dihydride complex demonstrated catalytic activity in hydrogenation and hydrosilylation.
- Kinetic studies revealed lower activity for the strontium dihydride complex compared to its calcium analogue.
Conclusions:
- Novel cationic strontium hydride complexes with a dinuclear core have been successfully synthesized.
- The catalytic performance of strontium complexes is influenced by the monomer-dimer equilibrium, leading to lower activity than calcium analogues.
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