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  • Effect of Carbon Chain Length on Nascent Yields of Stabilized Criegee Intermediates in Ozonolysis of a Series of Terminal Alkenes
Title: Effect of Carbon Chain Length on Nascent Yields of Stabilized Criegee Intermediates in Ozonolysis of a Series of Terminal Alkenes
The yields of stabilized Criegee intermediates (sCIs), CH2OO and RCHOO (C2H5CHOO, C3H7CHOO, C4H9CHOO, and C5H11CHOO), produced from ozonolysis of asymmetrical 1-alkenes (1-butene, 1-pentene, 1-hexene, and 1-heptene) were investigated at low pressures (5-16 Torr) using cavity ring-down spectroscopy (CRDS) and chemical titration with sulfur dioxide (SO2). By extrapolating the low-pressure measurements to zero-pressure limit, nascent sCI yields were obtained. Combined with our previous studies on ethene and propene ozonolysis, the nascent sCI yields demonstrated an intriguing trend of increasing with the addition of CH2 groups and eventually reached a plateau at around 31% for longer chain 1-alkenes. In particular, the fraction of stabilized CH2OO reached the plateau from 1-butene, indicating that CH2OO was produced with nearly the same internal energy distribution from 1-butene to 1-heptene. The comparison between the experiments and RRKM calculations suggests that the dissociation of primary ozonide (POZ) of O3 + ethene and propene can be treated by statistical theory, while that of O3 + 1-butene to 1-heptene is non-statistical and intramolecular vibrational redistribution (IVR) of the initial energy on the 1,2,3-trioxolane of POZ throughout the entire molecule was incomplete on the dissociation time scale.  more » « less
Award ID(s):
2155232
PAR ID:
10583665
Author(s) / Creator(s):
;
Publisher / Repository:
ACS
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
146
Issue:
35
ISSN:
0002-7863
Page Range / eLocation ID:
24591 to 24601
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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