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Synthesis and reversible reductive coupling of cationic, dinitrogen-derived diazoalkane complexes
John J Curley1, Tetsuro Murahashi, Christopher C Cummins
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 6-435, Cambridge, Massachusetts 02139, USA.
Inorganic Chemistry
|July 8, 2009
Summary
New cationic diazoalkane complexes were synthesized and characterized. Electrochemical reduction forms a C-C bonded dimer, with potential applications in charge-storage devices.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Materials Science
Background:
- Diazoalkane complexes are versatile synthetic intermediates.
- Understanding their electrochemical properties is crucial for developing new materials.
Purpose of the Study:
- To synthesize and characterize a series of cationic diazoalkane complexes.
- To investigate their electrochemical behavior and the formation of dimeric species.
- To explore potential applications in charge-storage devices.
Main Methods:
- Synthesis of novel cationic diazoalkane complexes.
- X-ray crystallography for structural determination.
- Infrared (IR) and Raman spectroscopy for vibrational analysis.
- Electrochemical investigations (cyclic voltammetry).
- Quantum chemical calculations.
Main Results:
- Successfully synthesized and characterized cationic diazoalkane complexes [4-RC(6)H(4)C(H)NNMo(N[t-Bu]Ar)(3)][AlCl(4)] for various R groups.
- Determined the structures of [1-H][AlCl(4)] and [1-NMe(2)][AlCl(4)] via X-ray crystallography.
- Identified C-N and N-N stretching modes using IR and Raman spectroscopy.
- Established a linear correlation between reduction potential and Hammett sigma parameter.
- Characterized the C-C bonded dimer formed upon electrochemical reduction.
- Described the odd-electron complex intermediate using electrochemical and computational methods.
- Demonstrated that the C-C bond in the dimer is redox-noninnocent and breaks upon oxidation.
Conclusions:
- The synthesized diazoalkane complexes exhibit interesting electrochemical properties.
- Electrochemical reduction leads to the formation of redox-active dimeric species.
- The redox-noninnocent nature of the C-C bond offers potential for applications in charge-storage devices.
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