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Updated: Jul 22, 2025
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Rh-Catalyzed Borylative Cyclization of Acrylate-Containing 1,6-Enynes.
Zhantao Yang1, Zhiqiang Yu1, Yulin He1
1Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian'ge Road, Anyang 455000, People's Republic of China.
This study introduces a new Rh-catalyzed reaction for synthesizing functionalized pyrrolidines from enynes. The method allows control over double bond geometry, creating valuable chemical structures.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Pyrrolidines are important heterocyclic compounds found in many natural products and pharmaceuticals.
- Efficient methods for constructing densely functionalized pyrrolidines with controlled stereochemistry are highly sought after.
Purpose of the Study:
- To develop a novel Rh-catalyzed carbocyclization/borylation reaction.
- To enable the synthesis of versatile pyrrolidines with tunable double bond geometry and quaternary stereocenters.
Main Methods:
- Utilized a rhodium catalyst for the regioselective and stereoselective transformation of acrylate-containing 1,6-enynes.
- Investigated the effect of alkyne substituents on the stereochemical outcome of the reaction.
Main Results:
- Successfully constructed pyrrolidines with either (Z) or uncommon (E) double bond geometry.
- Demonstrated that sterically hindered and conjugative aryl groups favor the formation of the (E)-isomer.
- Generated tetrasubstituted vinyl boronates containing an all-carbon quaternary stereocenter.
Conclusions:
- The developed method provides a general and practical route to diverse, highly functionalized pyrrolidines.
- The reaction offers a powerful tool for accessing complex molecular architectures with precise stereochemical control.
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