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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
A new approach to polycyclic azonia cations by ring-closing metathesis
Ana Núñez1, Ana M Cuadro, Julio Alvarez-Builla
1Departamento de Química OrgAnica, Universidad de AlcalA, 28871-AlcalA de Henares, Madrid, Spain.
Organic Letters
|July 13, 2007
Summary
This study demonstrates the successful application of ring-closing metathesis (RCM) using electron-deficient N-vinylpyridinium alkenes. The Hoveyda-Grubbs catalyst efficiently produced novel azonia cations with good yields.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Ring-closing metathesis (RCM) is a powerful carbon-carbon bond-forming reaction.
- Electron-deficient alkenes are typically challenging substrates for RCM.
- Azinium salts are versatile heterocyclic compounds.
Purpose of the Study:
- To explore the feasibility of using electron-deficient N-vinylpyridinium salts in RCM reactions.
- To synthesize novel tricyclic and tetracyclic azonia cations.
- To evaluate the efficacy of the Hoveyda-Grubbs catalyst in this transformation.
Main Methods:
- The study employed the ring-closing metathesis (RCM) reaction.
- N-vinyl-alpha-(2-styryl)azinium salts were used as substrates.
- The Hoveyda-Grubbs catalyst was utilized for the RCM reaction.
Main Results:
- The RCM reaction of N-vinyl-alpha-(2-styryl)azinium salts yielded various tricyclic and tetracyclic azonia cations.
- Moderate to good yields were achieved for the synthesized azonia cations.
- This represents the first reported instance of RCM involving highly electron-deficient N-vinylpyridinium alkenes.
Conclusions:
- The RCM reaction is a viable method for synthesizing complex azonia cations from electron-deficient alkenes.
- The Hoveyda-Grubbs catalyst is effective for this transformation.
- This work expands the scope of substrates applicable to RCM reactions.
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
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