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Updated: Jun 19, 2026

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Geometry dependence of the ring-opening E2 reaction in lactones
Xin Chen1, David A Walthall, John I Brauman
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
This study investigated gas phase bimolecular elimination (E2) reactions in lactones. Geometric distortion significantly impacts E2 reactions in smaller rings, outweighing ring strain effects.
Area of Science:
- Organic Chemistry
- Chemical Kinetics
Background:
- Gas phase bimolecular elimination reactions (E2) are fundamental in organic chemistry.
- Lactones are cyclic esters whose conformational flexibility can influence reaction pathways.
Purpose of the Study:
- To investigate the effect of geometric distortion on E2 reactions in lactones.
- To compare the influence of geometric distortion versus ring strain in lactone E2 reactions.
Main Methods:
- Studied gas phase E2 reactions of substituted and unsubstituted lactones.
- Analyzed kinetic energy dependence of E2 and proton transfer reactions.
Main Results:
- Geometric distortion significantly affects E2 reactions in four- and five-membered lactone rings.
- The impact of geometric distortion is more pronounced than ring strain.
- Six- and seven-membered rings showed minimal effects from geometric distortion.
Conclusions:
- Geometric distortion is a critical factor in the regioselectivity and rate of E2 reactions in lactones.
- Ring size plays a crucial role in how geometric constraints influence E2 reaction mechanisms.
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