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Journal of the Brazilian Chemical Society

Print version ISSN 0103-5053

Abstract

JUNKES, Berenice da S.; AMBONI, Renata D. de M. C.; YUNES, Rosendo A.  and  HEINZEN, Vilma E. F.. Application of the semi-empirical topological index in quantitative structure-chromatographic retention relationship (QSRR) studies of aliphatic ketones and aldehydes on stationary phases of different polarity. J. Braz. Chem. Soc. [online]. 2004, vol.15, n.2, pp. 183-189. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532004000200005.

The semi-empirical topological index, previously developed by Heinzen and Yunes, has been applied to predict the chromatographic retention of aliphatic ketones and aldehydes on stationary phases of different polarities (HP-1, HP-50, DB-210 and Innowax). Simple linear regressions between the retention indices and the semi-empirical topological indices (RI = a + bIET) were established for each stationary phase separately, showing satisfactory statistical parameters. The polarity of the stationary phases, indicated by McReynolds polarity (PR), is reflected in the coefficients of the equations (a and b) obtained for HP-1, HP-50 and DB-210, which linearly vary as the polarity of the stationary phase increases (intercept). Statistical analyses showed that the quantitative structure-chromatographic retention relationship (QSRR) models obtained on stationary phases of low-to-medium polarity (HP-1 and HP-50) have higher stability and predictive ability than those on polar stationary phases (DB-210 and Innowax). Thus, it can be concluded that the semi-empirical topological method, using only one descriptor, yielded better results on low-to-medium polarity stationary phases than methods that used multiple descriptors.

Keywords : QSRR; topological descriptor; semi-empirical topological index; aldehydes; ketones.

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