Supramolecular Polymerization and Functions of Isoxazole Ring Monomers

AbstractThe living supramolecular polymerization technique provides an exciting research avenue. However, in comparison with the thermodynamic spontaneous nucleation, using simple monomers to realize living supramolecular polymerization is hardly possible from an energy principle. This is because the activation barrier of kinetically trapped simple monomer (nucleation step) is insufficiently high to control the kinetics of subsequent elongation. Here, with the benefit of the confinement from the layered double hydroxide (LDH) nanomaterial, various simple monomers, (such as benzene, naphthalene and pyrene derivatives) successfully form living supramolecular polymer (LSP) with length control and narrow dispersity. The degree of polymerization can reach ~6000. Kinetics studies reveal LDH overcomes a huge energy barrier to inhibit undesired spontaneous nucleation of monomers and disassembly of metastable states. The universality of this strategy will usher exploration into other multifunctional molecules and promote the development of functional LSP.

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Supramolecular Systems Containing B–N Frustrated Lewis Pairs of Tris(pentafluorophenyl)borane and Triphenylamine Derivatives

Organic Materials ◽

10.1055/s-0041-1727235 ◽

2021 ◽

Vol 03 (02) ◽

pp. 174-183

Author(s):

P. Chidchob ◽

S. A. H. Jansen ◽

S. C. J. Meskers ◽

E. Weyandt ◽

N. P. van Leest ◽

...

Keyword(s):

Materials Science ◽

Supramolecular Polymers ◽

Frustrated Lewis Pairs ◽

Paramagnetic Resonance ◽

Donor And Acceptor ◽

Donor Acceptor ◽

Noncovalent Polymers ◽

Electron Paramagnetic ◽

Supramolecular Polymerization ◽

Lewis Pairs

The introduction of a chemical additive to supramolecular polymers holds high potential in the development of new structures and functions. In this regard, various donor- and acceptor-based molecules have been applied in the design of these noncovalent polymers. However, the incorporation of boron–nitrogen frustrated Lewis pairs in such architectures is still rare despite their many intriguing properties in catalysis and materials science. The limited choices of suitable boron derivatives represent one of the main limitations for the advancement in this direction. Here, we examine the use of the commercially available tris(pentafluorophenyl)borane with various triphenylamine derivatives to create supramolecular B–N charge transfer systems. Our results highlight the importance of a proper balance between the donor/acceptor strength and the driving force for supramolecular polymerization to achieve stable, long-range ordered B–N systems. Detailed analyses using electron paramagnetic resonance and optical spectroscopy suggest that tris(pentafluorophenyl)borane displays complex behavior with the amide-based triphenylamine supramolecular polymers and may interact in dimers or larger chiral aggregates, depending on the specific structure of the triphenylamines.

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ChemInform Abstract: Synthesis of the First Examples of the Imidazo[4,5-c]isoxazole Ring System.

ChemInform ◽

10.1002/chin.199934152 ◽

2010 ◽

Vol 30 (34) ◽

pp. no-no

Author(s):

George Tennant ◽

Christopher J. Wallis ◽

George W. Weaver

Keyword(s):

Ring System ◽

Isoxazole Ring

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Supramolecular Polymerization‐Induced Nanoassemblies for Self‐Augmented Cascade Chemotherapy and Chemodynamic Therapy of Tumour

Angewandte Chemie ◽

10.1002/ange.202103721 ◽

2021 ◽

Author(s):

Kuikun Yang ◽

Zhiqing Yang ◽

Ludan Yue ◽

Guocan Yu ◽

Xiangjun Zhang ◽

...

Keyword(s):

Supramolecular Polymerization

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Crystal structure of 5-{3-[2,6-dimethyl-4-(5-methyl-1,2,4-oxadiazol-3-yl)phenoxy]propyl}-N-(11-hydroxyundecyl)isoxazole-3-carboxamide hemihydrate

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989015007367 ◽

2015 ◽

Vol 71 (5) ◽

pp. 505-508 ◽

Cited By ~ 1

Author(s):

K. Salorinne ◽

T. Lahtinen

Keyword(s):

Crystal Structure ◽

Hydroxy Group ◽

Alkyl Chain ◽

Ring System ◽

Amide Bond ◽

Structural Units ◽

Isoxazole Ring ◽

Solvent Water ◽

Compound C ◽

Water Hydrogen

The title compound, C29H42N4O5·0.5H2O, comprises four structural units. A flexible propyloxy unit in agaucheconformation, with a –C(H2)—C(H2)—C(H2)—O– torsion angle of −64.32 (18)°, connects an isoxazole ring and an approximately planar phenyloxadiazole ring system [with a maxixmum devation of 0.061 (2) Å], which are oriented almost parallel to one another with a dihedral angle of 10.75 (7)°. Furthermore, a C11-alkyl chain with a terminal hydroxy group links to the 3-position of the isoxazole ringviaan amide bond. In the crystal, a half-occupancy solvent water molecule connects to a neighbouring moleculeviaan intermolecular O—H...O(water) hydrogen bond to the C11-alkyl chain hydroxy group.

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Ditopic hybrid ligands with an isoxazole ring in the central unit: synthesis, structural characterization and molecular modeling

Journal of Molecular Structure ◽

10.1016/j.molstruc.2021.131129 ◽

2021 ◽

pp. 131129

Author(s):

Bogdan-Ionel Bratanovici ◽

Corneliu Cojocaru ◽

Alina Nicolescu ◽

Mihaela Dascălu ◽

Gheorghe Roman

Keyword(s):

Molecular Modeling ◽

Structural Characterization ◽

Central Unit ◽

Isoxazole Ring ◽

Hybrid Ligands

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Living supramolecular polymerization of fluorinated cyclohexanes

Nature Communications ◽

10.1038/s41467-021-23370-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Oleksandr Shyshov ◽

Shyamkumar Vadakket Haridas ◽

Luca Pesce ◽

Haoyuan Qi ◽

Andrea Gardin ◽

...

Keyword(s):

Dipole Moment ◽

Self Assembly ◽

Materials Science ◽

Helical Structure ◽

The Self ◽

Supramolecular Polymers ◽

Aliphatic Compound ◽

Double Helical Structure ◽

Key Driver ◽

Supramolecular Polymerization

AbstractThe development of powerful methods for living covalent polymerization has been a key driver of progress in organic materials science. While there have been remarkable reports on living supramolecular polymerization recently, the scope of monomers is still narrow and a simple solution to the problem is elusive. Here we report a minimalistic molecular platform for living supramolecular polymerization that is based on the unique structure of all-cis 1,2,3,4,5,6-hexafluorocyclohexane, the most polar aliphatic compound reported to date. We use this large dipole moment (6.2 Debye) not only to thermodynamically drive the self-assembly of supramolecular polymers, but also to generate kinetically trapped monomeric states. Upon addition of well-defined seeds, we observed that the dormant monomers engage in a kinetically controlled supramolecular polymerization. The obtained nanofibers have an unusual double helical structure and their length can be controlled by the ratio between seeds and monomers. The successful preparation of supramolecular block copolymers demonstrates the versatility of the approach.

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