PARTITION-COEFFICIENTS OF NITROAROMATICS EXPRESSED IN TERMS OF THEIR MOLECULAR-SURFACE AREAS AND ELECTROSTATIC POTENTIALS

We have applied our general interaction properties function (GIPF) to the correlation analysis of octanol/water and acetonitrile/NaCl-satura ted-water partition coefficients, P-ow and P-aw for benzene, toluene, and nine of their nitro derivatives. The GIPF approach expresses physi cal properties in terms of molecular surface area in conjunction with several statistically-based quantities related to the surface electros tatic potential; all of these have been evaluated through ab initio SC F-MO calculations. Very good dual- and three-parameter relationships a re obtained for both log P-ow and log P-aw. We find that the positive potentials above and below the nitroaromatic rings are important deter minants of P-ow whereas the regions of negative potential are not high ly significant for either P-ow or P-aw.