Evaluation of vaporization enthalpies and liquid vapor pressures of cedrol, nerolidol, and 1-adamantanol by correlation gas chromatography

Abstract

The vaporization enthalpies and vapor pressures of (+)-cedrol and nerolidol are reported at T=298.15K using a series of alcohols as standards by correlation gas chromatography. Vaporization enthalpies at T=298.15K of (88.3±1.5, 91.4±1.5, 92.7±1.6) kJ·mol−1 were evaluated for (+)-cedrol, Z-nerolidol and E-nerolidol, respectively. Upon injection into the gas chromatograph, (+)-cedrol was partially converted to α- and β-cedrene, identified by GCMS and independent synthesis. Additionally, the vaporization enthalpy of 1-adamantanol evaluated as an unknown and then used as a standard, compared well to the value calculated from the sublimation, fusion and solid-solid phase transition enthalpies previously reported. Liquid vapor pressures of (+)-cedrol, Z-nerolidol, E-nerolidol and 1-adamantanol are also reported as a function of temperature. A vapor pressure of 187.9kPa is estimated for 1-adamantanol at the fusion temperature and the vapor pressure of solid 1-adamantanol at T=298.15K is reproduced within a factor of two of the literature value.