Predicting retention indices of aliphatic hydrocarbons on stationary phases modified with metallocyclams using quantitative structure-retention relationships

The quantitative structure-retention relationship (QSRR) was used to predict Kováts retention indices of forty-three volatile olefins on the chemically bonded stationary phase, containing 1,4,8,11-tetraazacycloteradecane (cyclam) complexes of copper(II) chloride. Retention indices were correlated with eleven descriptors derived from structures of olefins optimised using the molecular mechanics force field calculations (MM2). Descriptors were generated with the use of quantitative structure-activity relationships (QSAR), semi-empirical Austin Model 1 methods (AM1), and obtained from physicochemical databases. Five well-correlated models were built, with predictive coefficients of determination (R 2) values of 0.993 and 0.995. The dielectric energy (DE) descriptor was identified as being as important as the polarizability (P) descriptor in the process of separation of unsaturated olefins on stationary phases containing metal complexes. The DE index proved to be decisive in distinguishing between the geometric cis and trans isomers of the tested compounds.