Thermochemistry of 2-methylbenzoxazole and 2,5-dimethylbenzoxazole: an experimental and computational study

• Tipo: Artigo em Revista Científica Internacional
• Data: 2013

Autores

Ana L R Silva (Autor) Outra; Alvaro Cimas (Autor) Outra; Maria D M C R Ribeiro da Silva (Autor) FCUP

Revista

Título: Structural Chemistry

Vol. 24

Páginas: 1863-1872

ISSN: 1040-0400

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 12 Citações

Scopus - 12 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-006-JB8

DOI: 10.1007/s11224-013-0245-x

Abstract (EN): The standard (p degrees = 0.1 MPa) molar energies of combustion of 2-methylbenzoxazole and 2,5-dimethylbenzoxazole were measured by static-bomb combustion calorimetry. The standard molar enthalpies of vapourization, at T = 298.15 K, were obtained from high-temperature Calvet microcalorimetry. The experimental results enable the calculation of the standard molar enthalpies of formation in the gaseous state, at T = 298.15 K, for both compounds, being the results discussed in terms of structural and energetic contributions. The theoretically estimated gas-phase enthalpies of formation were calculated from high-level ab initio molecular orbital calculations at the G3(MP2)//B3LYP level of theory. The computed values compare very well with the experimental results obtained in this work and show that the 2,5-dimethylbenzoxazole is enthalpically the most stable compound. Furthermore, this composite approach was also used to obtain information about the gas-phase basicities, proton and electron affinities and adiabatic ionization enthalpies.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10