PREDICTION OF SOIL ADSORPTION COEFFICIENT KOC FOR PHENYLTHIO, PHENYLSULFINYL AND PHENYLSULFONYL ACETATES

Soil adsorption coefficients (Koc) have been measured by the batch equ ilibrium method for 25 phenylthio, phenylsulfinyl and phenylsulfonyl a cetates. Their Koc values were correlated with their HPLC capacity fac tors. The determination of Koc via HPLC capacity factor has been studi ed, including the effect of mobile phase composition on the correlatio n between Log Koc and Log K-1. Partial molecular connectivity indices (MCIs) have been calculated for these compounds and used to described their Log Koc values. Results demonstrate that while HPLC capacity fac tors (k'), molecular connectivity indices (MCIs) and octanol/water par tition coefficients (Kow) can correlate with Koc significantly, the k' , a theoretical capacity factor which has been obtained by extrapolati on of retention data in a binary solvent system to pure water eluent, has the most powerful ability in prediction of Koc for these studied c ompounds. (C) 1997 Published by Elsevier Science Ltd.