Enantioseparations of non-benzenoid and oligo-Tröger’s bases by HPLC on Whelk O1 column

Synthesis and Self‐Aggregation of Enantiopure and Racemic Molecular Tweezers Based on the Bicyclo[3.3.1]nonane Framework

“…Both systems have been synthesised as racemates, and derivatives of 1 and 2 have been isolated as enantiomerically pure forms by chromatography. [31,32] An attractive approach is to use an optically pure building block in the synthesis of an enantiomerically pure pair of tweezers, thus avoiding separation of enantiomers and diasteromers at the end. Such a building block is bicyclo-A C H T U N G T R E N N U N G [3.3.1]nonane-2,6-dione (3), which can be effectively resolved on a semilarge scale by kinetic resolution with Abstract: A pair of molecular tweezers (syn-4) that consists of quinoline and pyrazine units fused to a bicyclic framework is presented.…”

Determination of relative configuration of symmetrical bis-Tröger’s base derivatives

“…However, when no chiral separation is observed then diastereoiso- mer can be syn or anti, hence the possibility of unsuitable conditions to reach the resolution should be considered. Fortunately, the enantioseparation on the Whelk O1 column seems to be quite universal [22]. An analogous utilization of chiroptical properties was used recently to solve a similar structural problem of molecular tweezers [23].…”

Thiourea derivatives of Tröger’s base: synthesis, enantioseparation and evaluation in organocatalysis of Michael addition to nitroolefins

“…Incorrect designation of the absolute configuration of C(3) results from the fact that the original version of this CSP had an eleven-carbon linker, but substitution of it by the three-carbon linker results in the inversion of Cahn-Ingold-Prelog priorities at C(3). 13 In the recent studies, 14,15 we demonstrated that CSP Whelk O1 is rather versatile for the separation of Tröger's base analogues, in which the chiral center itself (stereogenic N-atom) serves as an H-bond acceptor. Moreover, systematic separation of a library of Tröger's base analogues allowed us to build a predictive model which is based on simple mechanistic considerations.…”