Site-Selective Pyridyl Alkyl Ketone Synthesis from N-Alkenoxypyridiniums through Boekelheide-Type Rearrangements
Qiang Liu1,2, Chao-Shen Zhang1, He Sheng1
1School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China.
Organic Letters
|July 8, 2020
Summary
Researchers developed a new alkylation method using N-alkenoxypyridiniums and the Boekelheide reaction. This breakthrough enables the synthesis of beta-2-pyridyl alkyl ketones, a reaction not achieved since 1954.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- The Boekelheide rearrangement is a known method for pyridine oxy-functionalization.
- Alkylation of pyridines via this rearrangement has not been achieved since 1954.
- N-alkenoxypyridinium functionalization is established for synthesizing carbonyl compounds.
Purpose of the Study:
- To develop a novel and efficient method for the alkylation of N-alkenoxypyridiniums.
- To synthesize beta-2-pyridyl alkyl ketones using the Boekelheide reaction.
Main Methods:
- Utilizing N-alkenoxypyridiniums as substrates.
- Applying the Boekelheide reaction conditions.
- Developing a novel alkylation strategy.
Main Results:
- Successfully achieved the alkylation of N-alkenoxypyridiniums.
- Synthesized beta-2-pyridyl alkyl ketones efficiently.
- Established a new synthetic route for this class of compounds.
Conclusions:
- The developed method provides a simple and efficient route to beta-2-pyridyl alkyl ketones.
- This work overcomes a long-standing limitation in pyridine chemistry.
- The study expands the synthetic utility of the Boekelheide rearrangement.
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