title: C3-symmetrical self-assembled structures investigated by vibrational circular dichroism.
abstract: We demonstrate by using vibrational circular dichroism (VCD) spectroscopy that it is possible to investigate the chirality of a supramolecular polymeric system in relatively dilute solutions. Chiral C(3)-symmetrical discotic molecules, based on a trialkylbenzene-1,3,5-carboxamide, form supramolecular columnar stacks with a right-handed helical structure in solution due to intermolecular hydrogen bonds. The handedness of the supramolecular chirality is determined using electronic spectroscopy measurements. Under dilute conditions (at 10(-3) M concentrations), it was also possible to probe the hydrogen bonding moieties with IR and VCD spectroscopy on these self-assembled structures. In combination with density functional theory (DFT) calculations, we could verify the preference for a right-handed chirality in the helical stacks and the nonplanar orientation of the carbonyl groups present in the molecule. This chiral arrangement is in agreement with the structure determined for a related benzene-1,3,5-tricarboxamide by X-ray diffraction. Chirality, 2008. (c) 2008 Wiley-Liss, Inc.
authors.affiliation: Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
authors.forename: Maarten M J
authors.initials: MM
authors.lastname: Smulders
authors.forename: Thierry
authors.initials: T
authors.lastname: Buffeteau
authors.forename: Dominique
authors.initials: D
authors.lastname: Cavagnat
authors.forename: Martin
authors.initials: M
authors.lastname: Wolffs
authors.forename: Albertus P H J
authors.initials: AP
authors.lastname: Schenning
authors.forename: E W
authors.initials: EW
authors.lastname: Meijer