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Abstract: This paper describes the peculiar co‐assembly supramolecular polymerization behavior of triphenylamine trisamide derivatives with d‐alanine (T‐ala) or glycine (T‐gly) moieties. Concentration and temperature‐dependent circular dichroism (CD) spectroscopy revealed that the heating curves of co‐assemblies obtained at various molar ratios of T‐ala to T‐gly exhibited two distinct transition temperatures. The first transition was due to the transformation from coiled helical bundles to single helical fibers without handedness. The second was due to a change from typical elongation to nucleation. These phenomena were confirmed by solvent‐dependent decoiling of coiled helical structures and concentration‐dependent morphological analysis. The two transitioning temperatures were dependent on the concentration of T‐ala in the co‐assemblies, suggesting that T‐ala concentration plays an important role in the formation of coiled helical bundles. Our study demonstrated the first observation of two distinct transition temperatures in supramolecular polymers. [ABSTRACT FROM AUTHOR]

The chiral stereoisomers of new non‐ionic dendritic amphiphiles self‐assemble in aqueous solution towards helical ribbons with opposite handedness. However, in the case of the meso‐compound, cylindrical assemblies are observed, as illustrated. Modelling suggests that they consist of right‐ or left‐handed helical molecular strands in equal distribution. The hydrophobic core of such a cylinder is sized to accommodate the hydrophobic tails. Only the head groups and the aromatic platforms, which contribute high density in transmission electron microscopy (TEM), are shown for clarity. The paper discusses stereochemical aspects upon supramolecular assembly of these new dendritic amphiphiles. More information can be found in the Full Paper by C. Böttcher, et al. on page 5629 ff. [ABSTRACT FROM AUTHOR]