M. A. V. R. D. Silva, Luís M. N. B. F. Santos, G. Pilcher
Jul 1, 1997
Citations
1
Influential Citations
7
Citations
Journal
The Journal of Chemical Thermodynamics
Abstract
Abstract The standard ( p °=0.1 MPa) molar enthalpies of formation of crystalline 1,1,1-trifluoro-4-(2-thienyl)-4-hydroxy-3-buten-2-one, HTTFA, and 1,1,1-trifluoro-4-(2-thienyl)-4-mercapto-3-buten-2-one, HTTFAS, at T =298.15 K were measured by rotating-bomb calorimetry and the standard molar enthalpies of sublimation at T =298.15 K were measured by microcalorimetry, with the following results: [Table] The results demonstrate an increase in stabilization energy of ≈(38.7±5.0) kJ·mol −1 in HTTFA compared with thiophene and that in these molecules, the intramolecular hydrogen bond energy (O–H . . . O), appears ≈20 kJ·mol −1 larger than for (S–H . . . O).