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Structural, thermochemical and kinetic insights on the pyrolysis of diketene to produce ketene.

ABSTRACT: Diketene (4-methylideneoxetan-2-one) is a precursor to the formation of either two molecules of ketene, or allene and CO₂ using pyrolysis techniques. It is not known experimentally which of these pathways is followed, or indeed if both are, during the dissociation process. We use computational methods to show that the formation of ketene has a lower barrier than formation of allene and CO₂ under standard conditions (by 12 kJ/mol). According to CCSD(T)/CBS, CBS-QB3 and M06-2X/cc-pVTZ calculations the formation of allene and CO₂ is favoured thermodynamically under standard conditions of temperature and pressure; however, kinetically the formation of ketene is favoured from transition state theory calculations at standard and elevated temperatures.

SUBMITTER: Poudel P

PROVIDER: S-EPMC10156866 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Structural, thermochemical and kinetic insights on the pyrolysis of diketene to produce ketene.

Poudel Pitambar P Masters Sarah L SL

Journal of molecular modeling 20230503 5

Diketene (4-methylideneoxetan-2-one) is a precursor to the formation of either two molecules of ketene, or allene and CO<sub>2</sub> using pyrolysis techniques. It is not known experimentally which of these pathways is followed, or indeed if both are, during the dissociation process. We use computational methods to show that the formation of ketene has a lower barrier than formation of allene and CO<sub>2</sub> under standard conditions (by 12 kJ/mol). According to CCSD(T)/CBS, CBS-QB3 and M06-2 ...[more]

PMID: 37133582

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