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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
Iron(I) in Negishi cross-coupling reactions
Christopher J Adams1, Robin B Bedford, Emma Carter
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
Journal of the American Chemical Society
|June 15, 2012
Summary
Iron(I) complexes are crucial for Negishi cross-coupling reactions. Researchers isolated and characterized key iron(I) intermediates, with one showing promise as an on-cycle catalyst for these important organic synthesis reactions.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Negishi cross-coupling reactions are vital for forming carbon-carbon bonds.
- The role of low-valent iron species in these reactions remains an active area of research.
Purpose of the Study:
- To demonstrate the significance of iron(I) in Negishi cross-coupling reactions.
- To isolate and characterize catalytically active iron(I) intermediates.
Main Methods:
- Synthesis and isolation of novel iron(I) complexes: [FeX(dpbz)2].
- Characterization using X-ray crystallography.
- Evaluation of catalytic activity in Negishi cross-coupling reactions.
Main Results:
- Isolation of iron(I) complexes with varying ligands (4-tolyl, Cl, Br).
- Crystallographic data confirmed the structure of the complexes.
- Complex 8b (iron(I) bromide) exhibited catalytic performance consistent with an on-cycle intermediate.
- Complex 7 (iron(I) 4-tolyl) appeared to be an off-cycle species.
Conclusions:
- Iron(I) plays a critical role in the catalytic cycle of Negishi cross-coupling reactions.
- The isolated iron(I) complexes provide insights into reaction mechanisms.
- Specific iron(I) species can act as effective on-cycle catalysts.
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