Calixsmaragdyrin: A Versatile Ligand for Coordination Complexes
Tamal Chatterjee1, Brian Molnar2, G G Theophall2
1Department of Chemistry, Indian Institute of Technology Bombay , Powai, Mumbai 400076, India.
Inorganic Chemistry
|March 24, 2017
Summary
Ruthenium(II) and BF2 complexes of calixsmaragdyrin were synthesized and characterized. Structural and spectroscopic studies revealed unique coordination and electronic properties, with DFT calculations supporting experimental findings.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Calixsmaragdyrin macrocycles are versatile platforms for developing novel metal complexes.
- Ruthenium(II) and BF2 complexes offer unique photophysical and electrochemical properties.
Purpose of the Study:
- To synthesize and characterize Ruthenium(II) and BF2 complexes of calixsmaragdyrin.
- To elucidate the structural, spectroscopic, and electronic properties of these complexes.
- To investigate their stability under redox conditions.
Main Methods:
- Synthesis of Ru(II) and BF2 complexes under simple reaction conditions.
- Characterization using HR-MS, 1D and 2D NMR, optical spectroscopy, and electrochemistry.
- Structural elucidation via X-ray crystallography and Density Functional Theory (DFT) calculations.
Main Results:
- The Ru(II) complex features a hexacoordinate Ru(II) ion within a distorted, dome-like calixsmaragdyrin macrocycle.
- The BF2 complex shows the BF2 unit bound to pyrrolic nitrogens of the dipyrrin moiety.
- Distinct absorption spectra were observed: Ru(II) complex (Soret band at 449 nm), BF2 complex (Soret band at 475 nm with Q-bands at 787 and 883 nm).
- DFT calculations confirmed structural similarity and electronic contributions of Ru(II) d orbitals to HOMO/LUMO.
- Time-Dependent DFT (TD-DFT) successfully reproduced experimental spectral shifts and transitions.
- Both complexes demonstrated stability under redox conditions.
Conclusions:
- The study successfully synthesized and characterized novel Ru(II) and BF2 calixsmaragdyrin complexes.
- The complexes exhibit distinct structural features and tunable photophysical properties.
- DFT calculations provide valuable insights into their electronic structure and spectral behavior.
- The stability of these complexes suggests potential applications in various fields.
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