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Updated: Jun 24, 2026
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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Transition Metal-Free Borata-Alkene/Alkyne Metathesis Enables Access to Cyclopentenes
Wenke Dong1,2, Haoyu Tian2, Yidan Hu3
1College of Chemistry and Chemical Engineering, Zhoukou Normal University, Zhoukou, Henan, Peoples's Republic of China.
Angewandte Chemie (International Ed. in English)
|June 23, 2026
Summary
This study introduces a novel, transition metal-free hetero-enyne metathesis using borata-alkenes. This method efficiently synthesizes diverse cyclopentene derivatives from simple precursors, expanding organic synthesis capabilities.
Area of Science:
- Organic Synthesis
- Catalysis
- Organoboron Chemistry
Background:
- Metathesis reactions are crucial for organic synthesis, primarily focusing on carbon-carbon bonds.
- Existing metathesis methods predominantly use transition metal catalysts.
- Incorporating heteroatoms and developing metal-free alternatives remain significant challenges.
Purpose of the Study:
- To develop a transition metal-free method for hetero-enyne metathesis.
- To utilize borata-alkenes as non-metal alkylidene surrogates.
- To synthesize diverse cyclopentene derivatives and explore cascade reactions.
Main Methods:
- Employing borata-alkenes as key reagents in metathesis reactions.
- Utilizing 1,1,1-triborylalkanes as readily accessible starting materials.
- Conducting mechanistic studies and density functional theory (DFT) calculations.
Main Results:
- Demonstrated a transition metal-free hetero-enyne metathesis for cyclopentene synthesis.
- Achieved chemodivergent products including boronic esters, borylsilylalkanes, and dienes.
- Developed sequential four-component couplings yielding ketones and enol ethers.
Conclusions:
- Borata-alkenes effectively act as non-metal alkylidene surrogates in metathesis.
- The developed method offers a versatile, metal-free route to substituted cyclopentenes.
- This work expands the scope of metathesis by incorporating heteroatoms and eliminating metal catalysts.
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