Spherical Supramolecular Minidendrimers Self-Organized in an “Inverse Micellar”-like Thermotropic Body-Centered Cubic Liquid Crystalline Phase
摘要:
An "inverse micellar"- or "water-in-oil"-like (similar to the lyotropic type I-II) thermotropic body-centered cubic (BCC) liquid crystal (LC) phase was discovered in a poly(ethyleneimine) with a degree of polymerization (DP) = 20 containing 3,3,5-tri(dodecyloxy)benzoyl minidendritic side groups. Fiber X-ray diffraction (XRD) experiments show that the extinction symbol of this phase is I--- and, alongside other evidence, suggested that the space group is Im (3) over bar m (Q(229)). These results point to a supramolecular inverse micellar-like structure with the polymer backbone and the benzoyl groups aggregated into globules located at the corners and the center of the unit cell. The n-alkyl groups radiate out of the aromatic part of the globule: and make up the continuos matrix of the lattice. The cubic unit cell parameter is a = 42.6 Angstrom. Upon shearing, the BCC phase aligns along the [111] direction. The BCC lyotropic Im (3) over bar m inverse micellar phase of I-II type has not yet been observed and the experiments reported here will access its design. The present is only the second "inverse micellar" thermotropic LC phase known. The first one was previously reported from our laboratories (Balagurusamy, V. S. K.; Ungar, G.; Percec, V.; Johansson, G. J. Am. Chem. Soc, 1997, 119, 1539) and has a Pm (3) over bar n symmetry. Both the Im (3) over bar m and the Pm (3) over bar n cubic lattices were self-organized from spherical supramolecular dendrimers. The BCC cubic LC lattice reported hen enriches the synthetic capabilities of dendritic building blocks.
Spherical Supramolecular Minidendrimers Self-Organized in an “Inverse Micellar”-like Thermotropic Body-Centered Cubic Liquid Crystalline Phase
摘要:
An "inverse micellar"- or "water-in-oil"-like (similar to the lyotropic type I-II) thermotropic body-centered cubic (BCC) liquid crystal (LC) phase was discovered in a poly(ethyleneimine) with a degree of polymerization (DP) = 20 containing 3,3,5-tri(dodecyloxy)benzoyl minidendritic side groups. Fiber X-ray diffraction (XRD) experiments show that the extinction symbol of this phase is I--- and, alongside other evidence, suggested that the space group is Im (3) over bar m (Q(229)). These results point to a supramolecular inverse micellar-like structure with the polymer backbone and the benzoyl groups aggregated into globules located at the corners and the center of the unit cell. The n-alkyl groups radiate out of the aromatic part of the globule: and make up the continuos matrix of the lattice. The cubic unit cell parameter is a = 42.6 Angstrom. Upon shearing, the BCC phase aligns along the [111] direction. The BCC lyotropic Im (3) over bar m inverse micellar phase of I-II type has not yet been observed and the experiments reported here will access its design. The present is only the second "inverse micellar" thermotropic LC phase known. The first one was previously reported from our laboratories (Balagurusamy, V. S. K.; Ungar, G.; Percec, V.; Johansson, G. J. Am. Chem. Soc, 1997, 119, 1539) and has a Pm (3) over bar n symmetry. Both the Im (3) over bar m and the Pm (3) over bar n cubic lattices were self-organized from spherical supramolecular dendrimers. The BCC cubic LC lattice reported hen enriches the synthetic capabilities of dendritic building blocks.
Thermodynamics of the Helical, Supramolecular Polymerization of Linear Self-Asembling Molecules: Influence of Hydrogen Bonds and π Stacking
作者:Fátima Aparicio、Luis Sánchez
DOI:10.1002/chem.201300553
日期:2013.8.5
The cooperative supramolecularpolymerization of 1 and 2 show very similar thermodynamic parameters (Δ, ΔS0, and Δ), but very different organization of the self‐assembling units to constitute helical structures. The results presented allow the quantification of the influence of the type and number of non‐covalent interactions in supramolecularpolymerization.
Pathway Complexity Versus Hierarchical Self‐Assembly in
<i>N</i>
‐Annulated Perylenes: Structural Effects in Seeded Supramolecular Polymerization
作者:Elisa E. Greciano、Beatriz Matarranz、Luis Sánchez
DOI:10.1002/anie.201801575
日期:2018.4.16
Studies were carried out on the hierarchicalself‐assembly versus pathway complexity of N‐annulated perylenes 1–3, which differ only in the nature of the linking groups connecting the perylene core and the side alkoxy chains. Despite the structural similarity, compounds 1 and 2 exhibit noticeable differences in their self‐assembly. Whereas 1 forms an off‐pathway aggregate I that converts over time
Biasing the Hierarchy Motifs of Nanotoroids: from 1D Nanotubes to 2D Porous Networks
作者:Jorge S. Valera、Hironari Arima、Cristina Naranjo、Takuho Saito、Natsuki Suda、Rafael Gómez、Shiki Yagai、Luis Sánchez
DOI:10.1002/anie.202114290
日期:2022.1.26
reported azobenzene dyads impedes their hierarchical self-assembly fromnanotoroids into nanotubes. In contrast, they organize into 2Dporousnetworks on substrate upon solution processing. Photoisomerization of azobenzene moieties allows efficient dissociation/reorganization of nanotoroids in solution, demonstrating their potential as photoresponsive 2Dporous nanosheets.