Handbook of Solvents - George Wypych - ChemTech - Ventech!

1006 An Li
Equation [14.21.2.8] can be helpful to obtain the b values for cosolvents not listed in
Table 14.21.2.2. In order to estimate cosolvency for such cosolvents, values of the intercept
a are also needed. However, values of a can be found in Table 14.21.2.2 for only about a
dozen cosolvents, and there is no reliable method for its estimation. To obtain a for a
cosolvent, a reasonable starting value can be log (V o*/V c), or -(0.92 + log V c). The average
absolute difference between a values listed in Table 14.21.2.2 and log (V o*/V c) is 0.18
(N=7) for alcohols and glycols, 0.59 (N = 6) for aprotic cosolvents, and > 1 for n-butylamine
and PEG400. 82
Table 14.21.2.2. Summary of regression results for relationship between σ and solute
log K ow
Cosolvent N a b R 2
log Kow range Ref.
Methanol 79 0.36±0.07 0.89±0.02 0.96 -4.53 ~ 7.31 80
Methanol 16 1.09 0.57 0.83 2.0 ~ 7.2 29
Methanol 16 1.07 0.68 0.84 n.a. 24
Ethanol 197 0.30±0.04 0.95±0.02 0.95 -4.90 ~ 8.23 80
Ethanol 107 0.40±0.06 0.90±0.02 0.96 -4.9 ~ 6.1 60
Ethanol 11 0.81 0.85 0.94 n.a. 24
1-Propanol 17 0.01±0.13 1.09±0.05 0.97 -3.73 ~ 7.31 80
2-Propanol 20 -0.50±0.18 1.11±0.07 0.94 -3.73 ~ 4.49 80
2-Propanol 9 0.63 0.89 0.85 n.a. 24
Acetone 22 -0.10±0.24 1.14±0.07 0.92 -1.38 ~ 5.66 80
Acetone 14 0.48 1.00 0.93 0.6 ~ 5.6* 24
Acetonitrile 10 -0.49±0.42 1.16±0.16 0.86 -0.06 ~ 4.49 80
Acetonitrile 8 0.35 1.03 0.90 n.a. 24
Dioxane 23 0.40±0.16 1.08±0.07 0.91 -4.90 ~ 4.49 80
Dimethylacetamide 11 0.75±0.30 0.96±0.12 0.87 0.66 ~ 4.49 80
Dimethylacetamide 7 0.89 0.86 0.95 n.a. 24
Dimethylformamide 11 0.92±0.41 0.83±0.17 0.73 0.66 ~ 3.32 80
Dimethylformamide 7 0.87 0.87 0.94 n.a. 24
Dimethylsulfoxide 12 0.95±0.43 0.79±0.17 0.68 0.66 ~ 4.49 80
Dimethylsulfoxide 7 0.89 0.87 0.95 n.a. 24
Glycerol 21 0.28±0.15 0.35±0.05 0.72 -3.28 ~ 4.75 80
Ethylene glycol 13 0.37±0.13 0.68±0.05 0.95 -3.73 ~ 4.04 80
Ethylene glycol 7 1.04 0.36 0.75 n.a. 24
Propylene glycol 62 0.37±0.11 0.78±0.04 0.89 -7.91 ~ 7.21 80