C-C σ-Bond Oxidative Addition and Hydrofunctionalization by a Macrocycle-Supported Diiron Complex.
Tianchang Liu1, Ryan P Murphy1, Patrick J Carroll1
1Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|July 26, 2022
Summary
This study demonstrates novel unassisted oxidative addition reactions for C-C bond activation using a diiron complex. These findings enable efficient C-C bond functionalization through catalytic cycles.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Synthetic Chemistry
Background:
- C-C bond activation is crucial for organic synthesis.
- Developing new catalytic methods for C-C bond functionalization remains a significant challenge.
Purpose of the Study:
- To report the first examples of unassisted C(sp)-C(sp2) and C(sp)-C(sp3) bond oxidative addition reactions.
- To explore the catalytic cycles for C-C sigma bond functionalization.
Main Methods:
- Utilizing a diiron complex, (3PDI2)Fe2(μ-N2)(PPh3)2 ([Fe2N]), for oxidative addition reactions.
- Reacting [Fe2N] with various diphenylacetylenes and phenylalkyne derivatives.
- Investigating subsequent hydrofunctionalization reactions with H2 or HBpin.
Main Results:
- Achieved unassisted C(sp)-C(sp2) bond oxidative addition with diphenylacetylenes.
- Observed selective C(sp)-C(sp2) or C(sp)-C(sp3) bond activation with phenylalkynes based on steric hindrance.
- Demonstrated catalytic hydrofunctionalization (hydrogenation and hydroboration) of C-C sigma bonds, regenerating the diiron complex.
Conclusions:
- The diiron complex facilitates unprecedented C-C bond oxidative addition reactions.
- This work provides a new catalytic pathway for C-C sigma bond functionalization, offering thermodynamically favorable products.
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