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Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
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Transition metal mediated carbonylative benzannulations
Wangze Song1, Stephanie A Blaszczyk, Jitian Liu
1School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA. wtang@pharmacy.wisc.edu.
Organic & Biomolecular Chemistry
|September 7, 2017
Summary
Carbonylative benzannulations convert carbon monoxide into benzene rings, crucial for pharmaceuticals. This review compares historical Fischer carbene methods with modern rhodium-catalyzed reactions.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Benzene rings are vital scaffolds in natural products and pharmaceuticals.
- Carbon monoxide (CO) is a key C1 feedstock but generally unreactive without catalysts.
- Historically, stoichiometric chromium and iron Fischer carbenes mediated carbonylative benzannulations.
Purpose of the Study:
- To review and compare historical Fischer carbene mediated carbonylative benzannulations with modern transition metal-catalyzed methods.
- To highlight the advancements in synthesizing benzene rings from carbon monoxide.
- To discuss mechanisms and applications of various carbonylative benzannulation strategies.
Main Methods:
- Review of literature on carbonylative benzannulations.
- Comparison of stoichiometric Fischer carbene methods with catalytic approaches.
- Analysis of reaction mechanisms including [3 + 2 + 1] and [5 + 1] cycloadditions.
Main Results:
- Transition metal catalysis, particularly rhodium, has enabled new carbonylative benzannulation pathways.
- Catalytic methods offer alternatives to stoichiometric reagents, improving efficiency and sustainability.
- Diverse cycloaddition strategies ([3 + 2 + 1], [5 + 1]) have been developed for benzene ring construction.
Conclusions:
- Modern transition metal-catalyzed carbonylative benzannulations represent a significant advancement over older Fischer carbene methods.
- These catalytic reactions provide efficient and versatile routes to valuable benzene-containing compounds.
- Further exploration of catalytic carbonylative benzannulations promises new synthetic possibilities.
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