enthalpy of vaporization

A series of 3-(1-R-5-phenyl-1H-pyrrol-2-yl)propanoic acids (R = H, Ar, Alk, Hetaryl) was obtained via the reaction of 4,7-dioxo-7-phenylheptanoic acid with amines. The enthalpies of vaporization and fusion of eight compounds were experimentally determined using differential thermal and thermogravimetric methods of analysis for the first time.

Combustion energies of esters (ethyl 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate; ethyl 6-methyl-4-(4-methylphenyl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate; ethyl 4-(4-methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate and ethyl 4-(6-methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate) were experimentally obtained using a bomb calorimetry. According to the experimental data, the enthalpies of combustion and the enthalpies of formation in a solid state were calculated.