for Physical Chemists by Physical Chemists


Chromatographic Hydrophobicity Index (CHI): Application to Agrochemical Research

Eric D. Clarke and Dianne B. Shirley, Syngenta, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, United Kingdom.

For ~ five years we have been utilising Klára Valkó’s chromatographic hydrophobicity index (CHI) to provide an initial assessment of log P octanol and pKa for exploratory agrochemicals (see Valkó et al, Anal. Chem. (1997) 69, 2022). Work to give indirect determinations of log P octanol and pKa from CHI values will be outlined and illustrated for a diverse range of agrochemical products. Data from two exploratory projects will be used to further explore the application of CHI to basic and acidic compounds. Finally we will discuss a multi-column/multi-organic solvent gradient matrix approach to determine Abraham Descriptors.

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Last modified: 28 April 2008