Thermochemical study of three dimethylpyrazine derivatives

• Type: Article in International Scientific Journal
• Date: 2008

Authors

Maria Ribeiro M C R da Silva (Author) FCUP; Joana I T A Cabral (Author) Other; Chelsea Givens (Author) Other; Stephanie Keown (Author) Other; Acree, WE (Author) Other

Journal

Title: Journal of Thermal Analysis and Calorimetry

Vol. 92

Pages: 73-78

ISSN: 1388-6150

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 7 Citations

Scopus - 7 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-004-0MH

DOI: 10.1007/s10973-007-8737-9

Abstract (EN): The standard (p(o)=0.1 MPa) molar enthalpies of formation, in the gaseous phase, at T=298.15 K, for 2,5-dimethylpyrazine (2,5-DMePz) and for the two dimethylpyrazine-N,N'-dioxide derivatives, 2,3-dimethylpyrazine-1,4-dioxide (2,3-DMePzDO) and 2,5-dimethyl-pyrazine-1,4-dioxide (2,5-DMcPzDO), were derived from the measurements of standard massic energies of combustion, using a static bomb calorimeter, and from the standard molar enthalpies of vaporization or sublimation, measured by Calvet microcalorimetry. The mean values for the molar dissociation enthalpy of the nitrogen-oxygen bonds, < DHmo >(N-O), were derived for both N,N'-dioxide compounds. These values are discussed in terms of the molecular structure of the two N,N'-dioxide derivatives and compared with < DHmo >(N-O) values previously obtained for other N-oxide derivatives.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6