A simple procedure for calculation of solvation enthalpy of compounds containing intramolecular hydrogen bond was developed. This procedure is based on the assumption that fragments of molecules containing intramolecular hydrogen bonds can be express as one group contribution. The proposed approach was verified by determination of the vaporization/sublimation enthalpies of poly-substituted phenols. Vaporization/sublimation enthalpies were obtained as difference between solution and solvation enthalpies in benzene. Solution enthalpies of thirteen compounds in benzene were measured in the present study. The obtained vaporization/sublimation enthalpies are in good agreement with values available in the literature. This promising result makes the solution calorimetry method preferable for quick estimations of enthalpy of phase transition, especially for explosive or compounds of low volatility.