Peroxido-bridged chiral double-decker dysprosium macrocycles
Chen Zhao1,2, Tingting Wang1,2, Xiaodong Liu1,2
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P. R. China. zhuzh@ciac.ac.cn.
Dalton Transactions (Cambridge, England : 2003)
|July 19, 2023
Summary
Researchers developed novel homochiral lanthanide peroxides, specifically dysprosium enantiomers. These molecules show potential for catalysis, with magnetic properties indicating differences in their crystal field environments.
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Materials Science
Background:
- Lanthanide peroxides are highly reactive in oxidative coupling of methane (OCM).
- The synthesis and structural characterization of molecular lanthanide peroxide species are limited.
- Homochiral molecule-based lanthanide peroxides have not been previously reported.
Purpose of the Study:
- To design and synthesize novel homochiral, side-on peroxido-bridged dinuclear hexaazamacrocyclic dysprosium enantiomers.
- To investigate the structural and magnetic properties of these newly synthesized dysprosium peroxide complexes.
- To explore the potential of these complexes in catalysis and understand their magnetic behavior.
Main Methods:
- Condensation reactions involving chiral diamines and dialdehydes to form macrocyclic ligands.
- Synthesis of dinuclear dysprosium peroxide complexes using hydrogen peroxide.
- Characterization using X-ray crystallography and alternating-current (ac) magnetic susceptibility measurements.
Main Results:
- Two pairs of homochiral, side-on peroxido-bridged dinuclear dysprosium enantiomers were successfully synthesized and structurally characterized.
- Complexes 1/2 exhibited frequency-dependent out-of-phase ac magnetic susceptibility peaks, indicating slow magnetic relaxation.
- Complexes 3/4 did not show magnetic peaks, suggesting a weaker axial crystal field compared to 1/2.
Conclusions:
- The successful synthesis of homochiral lanthanide peroxides opens new avenues in catalysis and molecular magnetism.
- The magnetic properties reveal distinct crystal field environments influenced by the ligand sphere.
- These findings contribute to the understanding of lanthanide peroxide chemistry and their potential applications.
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