The solubility of gases and vapours in dry octan-1-ol at 298 K

Ostwald solubility coefficients of 74 compounds in dry octan-1-ol at 298 K have been determined, and have been combined with literature values and add itional values we have calculated from solubilities in dry octan-1-ol and v apour pressures to yield a total of 161 log L-OctOH values at 298 K. These L-OctOH values are identical to gas-to-dry octan-1-ol partition coefficient s, often denoted as K-OA. Application of the solvation equation of Abraham to 124 values as a training set yielded a correlation equation with n = 124 , S.D. = 0.125, r(2) = 0.9970 and F = 7731. This equation was then used to predict 32 values of log L-OctOH as a test set, giving a standard deviation , S.D. of 0.131, an average absolute deviation of 0.085 and an average devi ation of -0.009 log units. The solvation equation for the combined 156 log L-OctOH values was LogL(OctOH) = -0.120 - 0.203R(2) + 0.560 pi (H)(2) +3.560 Sigma alpha (H)(2) + 0.702 Sigma beta (H)(2) +0.939logL(16), n = 156, r(2) = 0.9972, S.D. = 0.125 F = 10573, where, n is the number of data points (solutes), r the correlation coeffici ent, S.D. the standard deviation and F is the F-statistic. The independent variables are solute descriptors as follows: R-2 is an excess molar refract ion, pi (H)(2) the dipolarity/polarisability, Sigma alpha (H)(2) the overal l or summation hydrogen-bond acidity, Sigma beta (H)(2) the overall or summ ation hydrogen-bond basicity and L-16 is the Ostwald solubility coefficient on hexadecane at 298 K. The equation is consistent with similar equations for the solubility of gases and vapours into methanol, ethanol and propan-1 -ol. It is suggested that the equation can be used to predict further value s of log L-OctOH, for which the solute descriptors are known, to within 0.1 3 log units. (C) 2001 Elsevier Science Ltd. All rights reserved.