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Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
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Lewis Acid-Catalyzed Halonium Generation for Morpholine Synthesis and Claisen Rearrangement
Jeewani P Ariyarathna1, Nur-E Alom1, Leo P Roberts1
1Department of Chemistry and Biochemistry, School of Green Chemistry and Engineering, The University of Toledo, 2801 West Bancroft Street, Toledo, Ohio 43606, United States.
The Journal of Organic Chemistry
|February 10, 2022
Summary
This study presents a new synthetic strategy for morpholines and Claisen rearrangement products using a common halonium intermediate. The method offers high regioselectivity for various alkenes, enabling efficient synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Morpholine synthesis and Claisen rearrangements are fundamental transformations in organic chemistry.
- Developing regioselective methods for these reactions is crucial for efficient molecular construction.
Purpose of the Study:
- To disclose practical strategies for synthesizing morpholines and Claisen rearrangement products.
- To utilize the divergent reactivity of a common halonium intermediate for diverse synthetic outcomes.
Main Methods:
- Employing widely available alkenes in a Lewis acid-catalyzed halo-etherification process.
- Utilizing a common halonium intermediate to access different product classes.
Main Results:
- Achieved exceptional regioselectivity in the synthesis of morpholines and Claisen rearrangement products.
- Demonstrated the method's applicability to both activated and unactivated olefins.
- Mechanistic studies revealed a regiochemical kinetic resolution process.
Conclusions:
- The presented halo-etherification strategy provides a versatile route to valuable organic compounds.
- The divergent reactivity of the halonium intermediate allows for controlled synthesis of morpholines and Claisen products.
- The identified kinetic resolution offers insights into the reaction mechanism and selectivity.
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