Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Thermochemical and Theoretical Studies of Dimethylpyridine-2,6-dicarboxylate and Pyridine-2,3-, Pyridine-2,5-, and Pyridine-2,6-dicarboxylic Acids

Matos, M. A. R.[M. Agostinha R.], Morais, V. M. F.[Victor M. F.], da Silva, M. D. M. C. R.[Maria D. M. C. Ribeiro], Marques, M. C. F.[Marta C. F.], Sousa, E. A.[Emanuel A.], Castineiras, J. P.[Jorge P.], Santos, C. P.[Claudia P.], Acree, Jr., W. E.[William E.]
J. Chem. Eng. Data 2005, 50, 4, 1184-1191
ABSTRACT
The standard (pdeg ) 0.1 MPa) molar enthalpies of formation for gaseous pyridine-2,5-dicarboxylic acid, pyridine-2,6-dicarboxylic acid, and dimethylpyridine-2,6-dicarboxylate were derived from the standard molar enthalpies of combustion, in oxygen, at T ) 298.15 K, measured by static bomb combustion calorimetry, and the standard molar enthalpies of sublimation, at 298.15 K, measured by Calvet microcalorimetry: pyridine-2,5-dicarboxylic acid, -(580.6 ( 5.0) kJamol-1; pyridine-2,6-dicarboxylic acid, -(608.0 ( 6.1) kJamol-1; dimethylpyridine-2,6-dicarboxylate, -(562.4 ( 4.2) kJamol-1. The enthalpy of formation for crystalline pyridine-2,3-dicarboxylic acid was also derived from combustion calorimetry measurements as -(733.1 ( 2.0) kJamol-1. In addition, theoretical calculations using the density functional theory and the B3LYP/6-311G** hybrid exchange-correlation energy functional have been performed for these molecules in order to obtain the most stable geometries and to access their relative stabilities. The good correlation obtained between experimental and theoretical results allowed the estimation of the enthalpy of sublimation for pyridine-2,3-dicarboxylic acid.
Compounds
# Formula Name
1 CO2 carbon dioxide
2 N2 nitrogen
3 H2O water
4 O2 oxygen
5 C9H9NO4 2,6-pyridinedicarboxylic acid, dimethyl ester
6 C7H5NO4 2,3-pyridinedicarboxylic acid
7 C7H5NO4 2,5-pyridinedicarboxylic acid
8 C7H5NO4 pyridine-2,6-dicarboxylic acid
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 5
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Crystal
  • Gas
  • Static calorimetry
  • 1
  • POMD
  • 7
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Crystal
  • Gas
  • Static calorimetry
  • 1
  • POMD
  • 8
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Crystal
  • Gas
  • Static calorimetry
  • 1
  • RXND
  • 5
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Static bomb calorimetry
  • 1
  • RXND
  • 6
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Static bomb calorimetry
  • 1
  • RXND
  • 7
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Static bomb calorimetry
  • 1
  • RXND
  • 8
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Static bomb calorimetry
  • 1