Oxygen and sulfur heterocyclic compounds Perspectives on the energetic and structural relationships

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Vera L S Freitas (Author) Other; Maria D M C R Ribeiro da Silva (Author) FCUP

Journal

Title: Journal of Thermal Analysis and Calorimetry

Vol. 121

Pages: 1059-1071

ISSN: 1388-6150

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 20 Citations

Scopus - 21 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-00G-CME

DOI: 10.1007/s10973-015-4800-0

Abstract (EN): The knowledge of the thermodynamic properties of heterocyclic compounds, particularly the corresponding enthalpies of formation in condensed and gaseous states, enables a better understanding of their chemical behavior and, consequently, leads to an important background for the future development of their practical applications. Following our particular interest along the last decade on the establishment of energetic and structural relationships for heterocycle compounds with one or two benzene rings fused to a five- or six-membered ring containing oxygen or sulfur heteroatoms, we review the thermochemical data for derivatives of the following main structures: benzoxazole/benzothiazole, dibenzofuran/dibenzothiophene, xanthene/thioxanthene, and phenoxazine/phenothiazine. The experimental results, obtained by calorimetric and effusion techniques, namely static and rotating bomb combustion calorimetry, vacuum sublimation/vaporization drop microcalorimetry, and Knudsen effusion methods, were used to derive reliable thermodynamic values for the compounds studied. A complementary analysis of computational results for these molecules is presented. The agreement between the calculated and the experimental gas-phase enthalpies of formation represents a reinforcement on the validation of the established predictive schemes, supporting their use for related compounds whose energetic study is not available.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 13