An examination of vaporization, fusion and sublimation enthalpies of tolazoline using correlation gas chromatography and differential scanning calorimetry

Abstract

Tolazoline is a vasodilator that is used to treat spasms in peripheral blood vessels and to treat convulsive symptoms. The vaporization, fusion and sublimation enthalpies of tolazoline at T = 298.15 K have not been reported. Correlation gas chromatography experiments were first performed to identify appropriate standards that could be used for materials containing similar substituents. Subsequent correlations resulted in a vaporization enthalpy, \(\Delta_{\text{l}}^{\text{g}}\)H(298.15 K) of (89.9 ± 5.5) kJ mol−1 for tolazoline. A fusion enthalpy, \(\Delta_{\text{cr}}^{\text{l}}\)H(337.4 K) of (16.2 ± 0.4) kJ mol−1, was measured by differential scanning calorimeter and adjusted to T = 298.15 K. Combination of vaporization enthalpy and fusion enthalpy resulted in sublimation enthalpy, \(\Delta_{\text{cr}}^{\text{g}}\)H(298.15 K), of (103.9 ± 5.5) kJ mol−1.