Ozone-Assisted Oxidation of C5 Alkenes: Structural Effects on Criegee Intermediate Reaction Networks
Arden M Floyd1, Alec C DeCecco1, Yitong Zhai1
1Department of Chemistry, University of Central Florida, Orlando, Florida, USA.
Summary
Criegee intermediates from alkene-ozone reactions were studied. Alkene structure dictates their behavior, influencing atmospheric chemistry and combustion processes.
Area of Science:
- Atmospheric Chemistry
- Organic Chemistry
- Combustion Science
Background:
- Criegee intermediates (CIs) are crucial in atmospheric, organic synthesis, and combustion chemistry.
- Detecting CIs and their reactions is challenging, limiting understanding of their behavior in complex environments.
Purpose of the Study:
- To characterize the reactive behavior of CIs from ozone-assisted oxidation of trans-2-pentene and cyclopentene.
- To elucidate how alkene structure influences CI reaction pathways and product formation.
Main Methods:
- Utilized a jet-stirred reactor and molecular-beam high-resolution mass spectrometry with tunable synchrotron radiation.
- Employed photoionization efficiency curves and ab initio calculations for intermediate identification.
- Analyzed ozone-assisted oxidation products of specific C5-alkenes.
Main Results:
- Identified acetaldehyde oxide (CI-1) and propanal oxide (CI-2) from trans-2-pentene oxidation, undergoing isomerization and bimolecular reactions.
- Observed glutaraldehyde oxide (CI-3) from cyclopentene oxidation, primarily undergoing isomerization and decomposition.
- Discovered that alkene structure significantly controls CI reaction pathways and product complexity.
Conclusions:
- Alkene structure is a critical determinant of Criegee intermediate fate.
- Findings provide essential data for refining models of ozone-driven alkene oxidation.
- This research advances the understanding of CI chemistry in various environmental and synthetic contexts.
Keywords:
trans‐2‐penteneCriegee intermediatesacetaldehyde oxidecyclopenteneglutaraldehyde oxideozonolysispropanal oxideMore Related Videos
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