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Published on: December 6, 2021
Efficient catalysis of ammonia borane dehydrogenation
Melanie C Denney1, Vincent Pons, Travis J Hebden
1Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA.
Journal of the American Chemical Society
|September 14, 2006
Summary
Iridium pincer complexes catalyze the rapid, room-temperature dehydrogenation of ammonia borane (H3NBH3) to produce hydrogen gas (H2). A dormant catalyst form was identified and reactivated with H2.
Area of Science:
- Catalysis
- Inorganic Chemistry
- Materials Science
Background:
- Ammonia borane (H3NBH3) is a promising hydrogen storage material.
- Efficient dehydrogenation of ammonia borane is crucial for hydrogen production.
- Iridium complexes are known catalysts for various transformations.
Purpose of the Study:
- To investigate the catalytic activity of an iridium pincer complex for ammonia borane dehydrogenation.
- To identify and characterize intermediates in the catalytic cycle.
- To explore catalyst reactivation strategies.
Main Methods:
- Reaction of ammonia borane with an iridium pincer complex in tetrahydrofuran.
- Isolation and characterization of the metal borohydride complex.
- Reactivation studies using hydrogen gas.
Main Results:
- Rapid dehydrogenation of ammonia borane at room temperature was achieved.
- 1.0 equivalent of H2 and a polymeric species [NH2BH2]5 were generated.
- A dormant metal borohydride complex was isolated and shown to be reactivated by H2.
Conclusions:
- Iridium pincer complexes are highly effective catalysts for ammonia borane dehydrogenation.
- The catalytic cycle involves a dormant intermediate that can be regenerated.
- This work contributes to the development of efficient hydrogen production and storage systems.
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