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Published on: February 24, 2015
Fused metallacyclopropenes from alkynylphenols
Bingjie Fu1, Wei Bai1, Yue Zhao1
1School of Chemistry, Dalian University of Technology, Dalian, Liaoning, 116024, P. R. China. baiwei@dlut.edu.cn.
Researchers developed a new method for synthesizing fused osmacyclopropene complexes using alkynylphenols and osmium precursors. This work highlights the formation of key paramagnetic intermediates, showcasing selective carbon-carbon bond activation.
Area of Science:
- Organometallic Chemistry
- Synthetic Chemistry
- Coordination Chemistry
Background:
- Metallacyclopropenes are valuable synthetic intermediates derived from coordinated alkynes.
- Osmium complexes are known for their catalytic and synthetic applications.
Purpose of the Study:
- To develop a convenient synthesis for fused osmacyclopropene complexes.
- To investigate the formation of key paramagnetic alkyne-coordinated phenolate intermediates.
- To demonstrate selective C-C bond activation in osmium-alkyne systems.
Main Methods:
- Reaction of OsCl2(PPh3)3 with alkynylphenols.
- Isolation and characterization of paramagnetic alkyne-coordinated phenolate complexes.
- Formation of fused osmacyclopropene complexes.
Main Results:
- Successful synthesis of fused osmacyclopropene complexes 1 and 3.
- Identification of paramagnetic alkyne-coordinated phenolate complexes 2 as key intermediates.
- Demonstration of selective C-C bond activation under varying conditions.
Conclusions:
- A convenient synthetic route to fused osmacyclopropenes has been established.
- Paramagnetic intermediates play a crucial role in the formation of these complexes.
- The study provides insights into selective C-C activation mediated by osmium.
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