Abstract: A new approach to the quantification of the Lewis acidity and basicity of benzene and its derivatives was presented in this paper.The logarithm difference values of partition coefficients of the compounds in butyl ether/water and in cyclohexane/water system were used as the measurement of the acidity,while the logarithm difference values of the partition coefficients in trichloromethane/water and tetrachloromethane/water systems were used as the measurement of the basicity.The experimental results show a good correlation with the values in literatures.In addition,an estimation method for basicity was also developed.

Key words: Lewis acidity, Lewis basicity, Partition coefficients