P. 36-39 /

Pushing the limits of chiral amplification in supramolecular polymers

SEDA CANTEKIN, ANJA R. A. PALMANS*
*Corresponding author
Institute for Complex Molecular Systems, Laboratory of Macromolecular and Organic ChemistryTU Eindhoven, P.O. Box 513, Eindhoven, 5600 MB, The Netherlands

Abstract

N,N’,N’’-trialkylated-benzene-1,3,5-tricarboxamides(BTAs) self-assemble via strong, threefold α–helix typeintermolecular hydrogen bonding into well-defined,helical, one dimensional columnar aggregates. Theintroduction of a stereogenic centre into the alkyl sidechains of BTAs gives rise to strong Cotton effects in diluteapolar solutions indicating the preference for one helicalconformation over the other. Here, we summarise ourresearch on the influence of the position of the stereogeniccentre on the aggregate stability and the degree ofamplification of chirality in BTAs. In addition, we discloseour results on creating a preferred helical sense in BTAbasedsupramolecular polymers by introducing H/Disotope chirality into the alkyl side chains of BTAs at theα-position. We determine the relative stabilities of the leftandright-handed helical conformers formed by thesedeuterated molecules by performing a conformationalanalysis in different alkane solvents. Our findings showthat the subtle difference between the stabilities of thetwo conformers leads to a cooperative self-assemblyprocess, which is highly sensitive to the applied solvent.


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