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Strong NH···S hydrogen bonds in molybdoenzyme models containing anilide moieties
Taka-aki Okamura1, Kumiko Kunisue, Yui Omi
1Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan. tokamura@chem.sci.osaka-u.ac.jp
Dalton Transactions (Cambridge, England : 2003)
|March 29, 2013
Summary
New molybdenum complexes with anilide groups were synthesized. These compounds feature strong hydrogen bonds, leading to enhanced redox potential and catalytic activity in reducing trimethylamine N-oxide (Me3NO).
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Spectroscopy
Background:
- Molybdenum complexes are versatile in catalysis and materials science.
- Benzenedithiolate ligands offer unique electronic and structural properties.
- Anilide moieties can influence molecular conformation and reactivity.
Purpose of the Study:
- To synthesize and characterize novel monooxomolybdenum(IV) and dioxomolybdenum(VI) benzenedithiolate complexes.
- To investigate the structural and electronic effects of anilide substituents.
- To evaluate the catalytic activity of these complexes in the reduction of trimethylamine N-oxide (Me3NO).
Main Methods:
- Synthesis of molybdenum complexes.
- Characterization using nuclear magnetic resonance (NMR) spectroscopy (1H NMR).
- Spectroscopic analysis including UV-visible, infrared (IR), and Raman spectroscopy.
- Electrochemical studies to determine redox potentials.
Main Results:
- Successful synthesis and full characterization of molybdenum(IV) and molybdenum(VI) complexes.
- Evidence of strong intramolecular NH···S hydrogen bonds.
- Observation of a coplanar molecular structure.
- Significantly positive redox potentials were measured.
- Remarkable acceleration in the reduction of Me3NO in dimethylformamide (DMF).
Conclusions:
- The synthesized molybdenum complexes possess unique structural features due to intramolecular hydrogen bonding.
- These structural attributes contribute to enhanced electrochemical properties.
- The complexes demonstrate significant catalytic efficacy in Me3NO reduction, highlighting their potential applications.
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