Aromatic compounds octanol-water partition coefficients

Boublik, T., Fried, V., Hala, E. (1984) The Vapor Pressure of Pure Substances, 2nd revised Edition, Elsevier, Amsterdam, The Netherlands. Bowman, B. T., Sans, W. W. (1983) Determination of octanol-water partitioning coefficient (KqW) of 61 organophosphorus and carbamate insecticides and their relationship to respective water solubility (S) values. J. Environ. Sci. Health B18, 667-683. Bradley, R. S., Cleasby, T. G. (1953) The vapour pressure and lattice energy of some aromatic ring compounds. J. Chem. Soc. 1953, 1690-1692. 

Doucette, W. J., Andren, A. W. (1987) Correlation of octanol/water partition coefficients and total molecular surface area for highly hydrophobic aromatic compounds. Environ. Sci. Technol. 21, 521-524. 

MA Garcia, JC Diez-Masa, ML Marina. Correlation between the logarithm of capacity factors for aromatic compounds in micellar electrokinetic chromatography and their octanol-water partition coefficients. J. Chromatogr. A 742 251-256 (1996). 

In the example shown in Figure 1.1.1, the water solubilities and the octanol-water partition coefficients of benzene, chlorobenzene, and toluene are related directly through the QPPR Kov/ =f(Sw). In this case, only one property, the water solubility, is used as the predictor variable. Chlorobenzene, the query, is considered similar to toluene and benzene because it contains one aromatic ring. The chlorine substituent is hydrophobic and bulky, similar to the methyl group of toluene. If the range of compounds is expanded to n other compounds, the applicability of the QPPR is expanded to all compounds similar to the set of n compounds included in the training set. 

A correlation for less structurally related compounds was also developed by Amalric et al. (1996). To develop this correlation, meta- and para-substituted anisoles were studied. These aromatic compounds were substituted with F, Cl, N02, OH, and NH2 groups. The first-order degradation rate constant, kapf was predicted with the octanol/water partition coefficient (log Kow), Brown s constant (o+), and molar refractivity (MR) used as descriptors. The following correlation was developed ... 

The correlation was developed with a correlation coefficient of 0.903. The correlation was able to accurately predict the first-order degradation rate constants as a function of Brown s constant, the octanol/water partition coefficient, and molar refractivity. This correlation held for a broader class of aromatic compounds substituted at the meta and para positions, as compared to a simple substitution at one position on the aromatic ring. Table 9.6 lists the experimental and predicted values for the first-order degradation rate constants of substituted anisoles. 

Kaiser, K.L.E. (1983) A non-linear function for the approximation of octanol/water partition coefficients of aromatic compounds with multiple chlorine substitution. Chemosphere 12(9/10), 1159-1167. 

Helweg, C., Nielsen, T., Hansen, P.E. (1997) Determination of octanol-water partition coefficients of polar polycyclic aromatic compounds (N-PAC) by high performance liquid chromatography. Chemosphere 34, 1673-1684. 

Kaiser, K. L. E. (1983), A Non-linear Function for the Approximation of Octanol/Water Partition Coefficients of Aromatic Compounds with Multiple Chlorine Substitution, ... 

The fluorinated aromatic sulfonamides (31) bind tightly to carbonic anhydrase (CA) II enzyme and show their inhibitory activity. The activities for fluorinated inhibitors of carbonic anhydrase increase in the order of non-F, 2-F, 2,5-F2, 3,4,5-F3, 2,3,5,6-F4, and 2,3,4,5,6-Fs in 31 (1.8, 0.73, 0.55, 0.55, 0.53, 0.44 nM, respectively). The increased activity is due to their hydrophobicity and specific contacts between the fluoroaromatic ring and the Phe131 site of the protein [11]. The octanol/water partition coefficients (log P) measure the hydrophobicity of each compound and increase with the level of fluorine substitution. 

Figure 2.73 Organic compounds solubility in water vs. their octanol-water partition coefficient. 1-alcohols 2-ketones 3-esters 4-ethers 5-haloalkyls 6-alkines 7-alkenes 8-aromatics 9-alkanes 10-organophosphates 11-polychlorinated diphenyls (PCB) and DDT. (Chiou et al, 1982).

The solubility and octanol-water partition coefficients of a number of common liquid and solid aromatic compounds are given in Table IV. Except for chloroanilines and toluidines (20 C) and monohalobenzenes (30°C), solubilities are those observed at 25°C. The partition coefficients are those reported at room temperatures (normally between 20 and 25°C). For solid compounds, the re-... 

Cary T. Chiou TABLE IV Octanol-Water Partition Coefficients and Liquid and Supercooled Liquid Solubilities of Selected Aromatic Compounds ... 

Fig. 2. Correlation of octanol-water partition coefficient with water solubility for selected aromatic liquids and solids at 25°C log A ow = -0.862 log S +0.710 (r = 0.994, n - 36). The solubilities of solid compounds in the plot are those of their supercooled liquids at 25°C.

FIGURE 15.1 Comparison of a set of physicochemical properties associated with the aromatic compounds benzene and thiophene. The properties include molecular weight (MW), melting point (mp), boiling point (bp), octanol/water partition coefficient (Log P), molecular refractivity (MR), and density (d). 

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