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Determination and Analysis of Thermodynamic Properties of Methyl Methylanthranilate Isomers.

ABSTRACT: The enthalpies of formation in the gaseous phase of methyl 3-methylanthranilate and methyl 5-methylanthranilate were determined from experimental measurements of the corresponding standard energies of combustion, obtained from combustion calorimetry, and the standard enthalpies of vaporization and sublimation, obtained from Calvet microcalorimetry and Knudsen mass-loss effusion. A computational study, using the G3(MP2)//B3LYP composite method, has also been performed for the calculation of the gas-phase standard enthalpies of formation of those two molecules at T = 298.15 K, as well as for the remaining isomers, methyl 4-methylanthranilate and methyl 6-methylanthranilate. The results have been used to evaluate and analyze the energetic effect of the methyl substituent in different positions of the ring.

SUBMITTER: Silva CAO

PROVIDER: S-EPMC10534601 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Determination and Analysis of Thermodynamic Properties of Methyl Methylanthranilate Isomers.

Silva Carlos A O CAO Freitas Vera L S VLS da Silva Maria D M C Ribeiro MDMCR

Molecules (Basel, Switzerland) 20230918 18

The enthalpies of formation in the gaseous phase of methyl 3-methylanthranilate and methyl 5-methylanthranilate were determined from experimental measurements of the corresponding standard energies of combustion, obtained from combustion calorimetry, and the standard enthalpies of vaporization and sublimation, obtained from Calvet microcalorimetry and Knudsen mass-loss effusion. A computational study, using the G3(MP2)//B3LYP composite method, has also been performed for the calculation of the g ...[more]

PMID: 37764462

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