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Hydrazone-based cobalt complexes toward multielectron redox and spin crossover.
Wei Huang1, Yujie Li1, Juan Yong1
1Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, Collaborative Innovation Center of Advanced Catalysis & Green Manufacturing, School of Petrochemical Engineering, Changzhou University Changzhou Jiangsu 213164 China wudy@cczu.edu.cn.
RSC Advances
|May 11, 2022
Summary
New cobalt complexes with hydrazone ligands show tunable spin crossover behavior. Ligand modifications influence the metal
Area of Science:
- Coordination Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Cobalt complexes are versatile in coordination chemistry.
- Spin crossover (SCO) materials exhibit tunable electronic properties.
- Hydrazone ligands offer tunable coordination environments.
Purpose of the Study:
- To synthesize and characterize novel bis-homoleptic cobalt complexes.
- To investigate the impact of ligand modification on cobalt complex properties.
- To explore redox-switchable spin crossover in cobalt(II) systems.
Main Methods:
- Synthesis of hydrazone-based ligands.
- Preparation of bis-homoleptic cobalt complexes.
- Variable temperature magnetic susceptibility measurements.
- Electrochemical analysis.
Main Results:
- A Co(III) complex with deprotonated ligands adopted a diamagnetic ground state.
- Co(II) complexes with non-deprotonated ligands exhibited gradual spin crossover.
- Ligand substituents tuned the spin crossover behavior and redox potentials.
- Redox-switchable spin crossover was demonstrated in the cobalt(II) system.
Conclusions:
- Ligand deprotonation and substituent effects significantly influence cobalt complex spin states.
- Hydrazone ligands provide a platform for designing redox-switchable spin crossover materials.
- The study highlights the interplay between ligand design and metal center properties.
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