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Published on: February 7, 2019
Hangman salen platforms containing dibenzofuran scaffolds
Jenny Y Yang1, Shih-Yuan Liu, Ivan V Korendovych
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA.
Researchers synthesized novel "Hangman" ligands and observed a high-valent metal oxo intermediate using hydrogen peroxide. This intermediate
Area of Science:
- Catalysis
- Inorganic Chemistry
- Organic Synthesis
Background:
- Hangman ligands are crucial in catalysis.
- Understanding metal oxo intermediates is key for oxidation reactions.
Purpose of the Study:
- To synthesize novel Hangman ligands with dibenzofuran spacers.
- To investigate the formation and reactivity of high-valent metal oxo intermediates.
- To explore their potential in water-splitting chemistry.
Main Methods:
- Synthesis of functionalized salen ligands with dibenzofuran spacers.
- Stopped-flow kinetic studies using hydrogen peroxide as an oxidant.
- Evaluation of catalytic activity in hydrogen peroxide disproportionation and olefin epoxidation.
Main Results:
- Successfully synthesized Hangman ligands with differentially extended acid functionalities.
- Identified a high-valent metal oxo intermediate at the Hangman platform.
- Demonstrated the oxo species' activity in hydrogen peroxide disproportionation and olefin epoxidation.
Conclusions:
- The distance between the acid group and metal center influences oxo species activity.
- Hangman oxo complexes offer a promising pathway for developing water-splitting catalysts.
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