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Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
14.6K
Iron(II) spin crossover complexes with diaminonaphthalene-based Schiff base-like ligands: mononuclear complexes
Charles Lochenie1, Julia Heinz, Wolfgang Milius
1Inorganic Chemistry II, Universität Bayreuth, Universitätsstraße 30, NW I, 95440 Bayreuth, Germany. weber@uni-bayreuth.de.
Dalton Transactions (Cambridge, England : 2003)
|September 30, 2015
Summary
New iron complexes with extended π-systems exhibit spin crossover behavior. Cooperative interactions, driven by C-Hπ and C-HO bonds, create wide thermal hysteresis loops up to 10 K.
Area of Science:
- Coordination Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Schiff base ligands are versatile building blocks in coordination chemistry.
- Spin crossover (SCO) materials exhibit temperature- or light-induced changes in spin state.
- Extended π-systems in ligands can influence intermolecular interactions and material properties.
Purpose of the Study:
- To synthesize novel Schiff base-like ligands with extended π-systems.
- To investigate the spin crossover behavior of their corresponding iron(II) complexes.
- To understand the role of extended aromatic systems in mediating cooperative interactions.
Main Methods:
- Synthesis of Schiff base-like ligands and iron(II) complexes.
- Single crystal X-ray structure analysis.
- X-ray powder diffraction.
- Magnetic measurements.
Main Results:
- Successful synthesis of new Schiff base-like ligands and their iron(II) complexes.
- Observation of spin crossover behavior in some iron(II) complexes featuring N-heterocycles as axial ligands.
- Identification of C-Hπ and C-HO interactions as key factors influencing cooperative effects.
- Demonstration of up to 10 K wide thermal hysteresis loops attributed to these interactions.
Conclusions:
- Extended π-systems in Schiff base-like ligands can promote cooperative interactions in iron complexes.
- C-Hπ and C-HO interactions play a crucial role in achieving significant thermal hysteresis in spin crossover materials.
- These findings contribute to the design of novel molecular switches and functional materials.
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