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Updated: May 27, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Tetrakis(imino)pyracene complexes exhibiting multielectron redox processes.
Kalyan V Vasudevan1, Michael Findlater, Ignacio Vargas-Baca
1Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Journal of the American Chemical Society
|December 2, 2011
Summary
The study explored redox behavior differences between bis(imino)acenaphthene (BIAN) and tetrakis(imino)pyracene (TIP) ligands. Reactions with p-block elements showed TIP ligands accept three to four electrons, influenced by bonding interactions.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Computational Chemistry
Background:
- Bis(imino)acenaphthene (BIAN) and tetrakis(imino)pyracene (TIP) are nitrogen-containing ligands with distinct functionalities.
- Understanding ligand redox behavior is crucial for designing novel materials and catalysts.
- The electronic properties of p-block elements can be tuned through coordination with organic ligands.
Purpose of the Study:
- To investigate and compare the redox properties of monofunctional BIAN and bifunctional TIP ligands.
- To explore the electron transfer dynamics between p-block elements and the TIP ligand.
- To elucidate the role of bonding interactions in dictating the extent of electron transfer.
Main Methods:
- Synthesis of TIP ligand complexes with p-block elements (PI(3), TeI(4), BI(3)).
- Electrochemical analysis to determine redox potentials and electron transfer.
- Density Functional Theory (DFT) calculations to model electronic structure and bonding.
Main Results:
- Reactions of TIP with PI(3), TeI(4), and BI(3) resulted in products with three or four electron transfer events.
- DFT calculations confirmed that the degree of electron transfer is directly correlated with the strength of the element-TIP bonding interactions.
- Differences in redox behavior between BIAN and TIP ligands were highlighted, with TIP exhibiting greater electron acceptance.
Conclusions:
- The bifunctional TIP ligand demonstrates significant electron-accepting capabilities, facilitating multi-electron transfer processes.
- Element-TIP bonding interactions are a key determinant of electron transfer extent in these systems.
- This study provides fundamental insights into the redox chemistry of polycyclic aromatic nitrogen heterocycles and their interactions with p-block elements.
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