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Thermochemical studies of epoxides and related compounds.

ABSTRACT: Gas-phase heats of formation for the four butene oxide isomers are reported. They were obtained by measuring the condensed-phase heat of reduction to the corresponding alcohol using reaction calorimetry. Heats of vaporization were determined and allow gas-phase heats of formation to be obtained. The experimental measurements are compared to calculations obtained using a variety of computational methods. Overall, the G3 and CBS-APNO methods agree quite well with the experimental data. The influence of alkyl substituents on epoxide stability is discussed. Comparisons to alkenes, cyclopropanes, aziridines, thiiranes, and phosphiranes are also made. Isodesmic-type reactions were used to determine strain energies of the epoxides and related compounds with various substituents.

SUBMITTER: Morgan KM

PROVIDER: S-EPMC3671579 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Thermochemical studies of epoxides and related compounds.

Morgan Kathleen M KM Ellis Jamie A JA Lee Joseph J Fulton Ashley A Wilson Shavonda L SL Dupart Patrick S PS Dastoori Rosanna R

The Journal of organic chemistry 20130422 9

Gas-phase heats of formation for the four butene oxide isomers are reported. They were obtained by measuring the condensed-phase heat of reduction to the corresponding alcohol using reaction calorimetry. Heats of vaporization were determined and allow gas-phase heats of formation to be obtained. The experimental measurements are compared to calculations obtained using a variety of computational methods. Overall, the G3 and CBS-APNO methods agree quite well with the experimental data. The influen ...[more]

PMID: 23551240

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