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Competition between reaction and intramolecular energy redistribution in solution: observation and nature of nonstatistical dynamics in the ozonolysis of vinyl ethers.

ABSTRACT: Experimental product ratios in ozonolyses of alkyl vinyl ethers in solution do not fit with expectations based on statistical rate theories. The selectivity among cleavage pathways increases with the size of the alkyl group but to an extent that is far less than RRKM theory would predict. Trajectory studies account for the observed selectivities and support a mechanism involving a competition between cleavage of the primary ozonide and intramolecular vibrational energy redistribution. A statistical model is presented that assumes that RRKM theory holds for a molecular subset of the primary ozonides, allowing the rates of energy loss from the ozonides to be estimated from the observed product ratios.

SUBMITTER: Quijano LM

PROVIDER: S-EPMC3164887 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Competition between reaction and intramolecular energy redistribution in solution: observation and nature of nonstatistical dynamics in the ozonolysis of vinyl ethers.

Quijano Larisa Mae M LM Singleton Daniel A DA

Journal of the American Chemical Society 20110815 35

Experimental product ratios in ozonolyses of alkyl vinyl ethers in solution do not fit with expectations based on statistical rate theories. The selectivity among cleavage pathways increases with the size of the alkyl group but to an extent that is far less than RRKM theory would predict. Trajectory studies account for the observed selectivities and support a mechanism involving a competition between cleavage of the primary ozonide and intramolecular vibrational energy redistribution. A statisti ...[more]

PMID: 21812422

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