Abstract: MATH/CHEM/COMP 2002, Dubrovnik, June 24-29, 2002







Darko KONTREC, Vladimir VINKOVIC, and Vitomir SUNJIC



Rudjer Boskovic Institute, P. O. Box 180, 10002 Zagreb, Croatia



Aesthetically motivated supramolecular synthesis based on symmetry, topology, and network properties represent a distinct aim for subjects such as crystal engineering or chiral recognition. Enantiorecognition represents a bottom line process which enables separation of enantiomers by chromatography on chiral stationary phases (CSPs).











I                                                                                             II











































IV                                                                                              V



CSPs based on assemblies of planar, homo- or heteroaromatic branching units, usually with one or two chiral subunits and a spacer that enables binding to silica gel, are known as Pirkle-type or brush-type CSPs and are repeatedly reported.1-3We entered the field of enantioseparation by developing two main groups of CSPs; the first group (I-III) is based on derivatives of persubstituted, p-basic aromatic ring,4-6 the second CSPs (IV-V) are derived from 4-substituted 3,5-dinitrobenzoic acid derivatives, which serve as the p-acidic branching unit.7

Rationale behind the synthesis of over 50 representatives of CSPs I-V, and correlation of their enantioseparation ability to their conformational and structural properties, in particular H-bonding ability and p-acid/base interactions, will be presented. Separation of specific groups of racemic analytes, as e.g. a-aryloxypropionic acids, 4-substituted 1,4-dihydropyrimidines, and 1,4-benzodiazepines is achieved with specifically designed CSPs; mechanisms of enantioseparation, and the observed enantiomerization of configurationally unstable analytes will be discussed.




1 W. H. Pirkle, J. Chromatogr. A 749 (1996) 19-24.


2 S. Allenmark, V. Schurig, J. Mater. Sci. 7 (1997) 1995-1963.


3 E. R. Francotte, Chimia 51 (1997) 717-725.


4 I. Novak, B. Kovac, D. Kontrec, V. Sunjic, J. Electron Spectr. 199 (2000) 281-286.


5 D. Kontrec, V. Vinkovic, A. Lesac, V. Sunjic, A. Aced, Enantiomer 5 (2000) 333-344.


6 a D. Kontrec, A. Abatangelo, V. Vinkovic, V. Sunjic, Chirality 13 (2001) 294-301; b V. Vinkovic, D. Kontec, V. Sunjic, L. Navarini, F. Zanetti, O. Azzolina, Chirality 13 (2001) 581-587; c A. Abatangelo, F. Zanetti, L. Navarini, D. Kontrec, V: Vinkovic, V. Sunjic, Chirality 13 (2001) 984-992.


7 B. Zafirova, D. Kontrec, V. Vinkovic, V. Sunjic, Chirality (2002) submitted.