The fusion thermochemistry of self-associated aromatic compounds at 298.15 K studied by solution calorimetry

Abstract

The solution calorimetry approach for determination of the fusion enthalpy at 298.15 K of aromatic compounds not capable of self-association was extended to those forming intermolecular hydrogen bonds. Two groups of such compounds, namely phenol and aniline derivatives, were investigated. From the solution enthalpies at 298.15 K of phenols in anisole and aromatic amines in aniline the fusion enthalpies at 298.15 K can be derived. Validity of the solution calorimetry approach was checked using differential scanning calorimetry and fast scanning calorimetry.The solution enthalpies of 12 compounds in anisole and aniline at 298.15 K and the fusion enthalpies at the melting temperature of 9 compounds were measured. Resorcinol, 1,6-dihydroxynaphthalene, and 1,3-diaminobenzene were additionally studied using fast scanning calorimetry. The molar heat capacities of crystalline 1,6-dihydroxynaphthalene and liquid 1,3-diaminobenzene were measured by conventional DSC in the wide temperature range.