Prediction of the Normal Boiling Points and Enthalpy of Vaporizations of Alcohols and Phenols Using Topological Indices

Resumo

Establishing quantitative correlations between various molecular properties and chemical structures is of great technological importance for environmental and medical aspects. These approaches are referred to as Quantitative Structure-Property Relationships (QSPR), which relate the physico-chemical or thermodynamic properties of compounds to their structures. The main goal of QSPR studies is to find a mathematical relationship between the property of interest and a number of molecular descriptors derived from the structure of the molecule. The current study presents the relationship between the Randic′ (¹χ), Balaban (J),Wiener polarity (W_p), Hyper Wiener (WW), Szeged (Sz), Harary (H) and Wiener (W) indices to the normal boiling points (T_bp, K) and the standard enthalpies of vaporization (ΔH_vap⁰, kJ/mol^–1) of 227 alcohols and phenols. The multiple linear regression (MLR) and backward methods were employed to give the QSPR models. After MLR analysis, we studied the validation of linearity between the molecular descriptors in the best models for used properties. The results have shown that three descriptors (W, ¹χ, J) could be efficiently used for estimating the normal boiling points, and two descriptors (¹χ, J) could be used for modeling and predicting the standard enthalpies of vaporization of considered compounds.