A High-Symmetry Coordination Cage from 38- or 62-Component Self-Assembly

The design of new chiral materials usually requires stereoselective organic synthesis to create molecules with chiral centers. Less commonly, achiral molecules can self-assemble into chiral materials, despite the absence of intrinsic molecular chirality. Here, we demonstrate the assembly of high-symmetry molecules into a chiral van der Waals structure by synthesizing crystals of C60(SnI4)2 from icosahedral buckminsterfullerene (C60) and tetrahedral SnI4 molecules through spontaneous self-assembly. The SnI4 tetrahedra template the Sn atoms into a chiral cubic three-connected net of the SrSi2 type that is held together by van der Waals forces. Our results represent the remarkable emergence of a self-assembled chiral material from two of the most highly symmetric molecules, demonstrating that almost any molecular, nanocrystalline, or engineered precursor can be considered when designing chiral assemblies.

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The cubic polyhedral oligomeric silsesquioxanes based hybrid materials have a wide variety of applications, including drug administration, gene therapy, biological imaging, and bone regeneration

10.31219/osf.io/9peq8 ◽

2021 ◽

Author(s):

Moataz Dowaidar

Keyword(s):

Gene Therapy ◽

Bone Regeneration ◽

Hybrid Materials ◽

Drug Administration ◽

Self Assembly ◽

Building Blocks ◽

Research Field ◽

Biological Imaging ◽

High Symmetry ◽

Polyhedral Oligomeric Silsesquioxanes

The cubic polyhedral oligomeric silsesquioxanes (POSS), which has a well-defined compact frame, high symmetry, and various modified organic substitutes, has received much interest as one of the most critical building blocks for hybrid nanomaterials and self-assembly driven amphiphilics. This work assessed current molecular design advances, solution self-assembly capabilities, and anticipated biological applications of POSS-based hybrid materials. By adopting controlled/living polymerization techniques and considerable advancements in efficient chemical coupling techniques, preparation techniques for topological POSS-based hybrid materials have become a rapidly increasing research field with future advances. The resultant POSS hybrids with various functional groups help to create complicated, unique self-assembled morphologies in solutions, induced by discrete intermolecular interactions. POSS-based hybrid materials have a wide variety of applications, including drug administration, gene therapy, biological imaging, and bone regeneration, due to their particular benefits (such as high biocompatibility, low cytototoxicity, and good degradability) and simplicity of self-assembly behaviour.

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Late Stage Diversification of an Unsymmetrical Ligand Scaffold for Multi-functional cis-Pd2L4 Nanocage Libraries

10.26434/chemrxiv.13246715.v1 ◽

2020 ◽

Author(s):

James Lewis

Keyword(s):

Self Assembly ◽

Late Stage ◽

Combinatorial Libraries ◽

The Self ◽

High Symmetry ◽

Diversification Strategy ◽

Supramolecular Architectures ◽

Common Precursor ◽

Potential Applications ◽

Low Symmetry

Although many impressive metallo-supramolecular architectures have been reported, they tend towards high symmetry structures and avoid extraneous functionality to ensure high-fidelity in the self-assembly process. This minimalist approach, however, limits the range of accessible structures and thus their potential applications. Herein is described a late stage diversification strategy towards ligand scaffolds that are both low symmetry and incorporate exohedral functional moieties. Key to this design is the use of CuAAC chemistry, as the triazole is capable of acting as both a coordinating heterocycle and a tether between the ligand framework and functional unit simultaneously. In this manner a common precursor was used to generate ligands with various functionalities, allowing control of electronic properties, whilst maintaining the core structure of the resultant cis-Pd2L4 nanocage assemblies. The isostructural nature of the scaffold frameworks enabled formation of combinatorial libraries from the self-assembly of ligand mixtures, generating multi-functional, low-symmetry architectures.

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Generalizing the Chiral Self-Assembly of Spheres and Tetrahedra to Non-Spherical and Polydisperse Molecules in (C70)x(C60)(1-x)(SnI4)2

10.26434/chemrxiv.14270012.v1 ◽

2021 ◽

Author(s):

Daniel B. Straus ◽

Robert J. Cava

Keyword(s):

Solid Solution ◽

Self Assembly ◽

Lattice Parameter ◽

Nonspherical Particles ◽

High Symmetry ◽

Chiral Phase ◽

Cubic Lattice ◽

Vegard’S Law ◽

Chiral Materials ◽

Chiral Crystals

We describe the spontaneous chiral self-assembly of C70 with SnI4 as well as a mixture of C60 and C70 with SnI4. Macroscopic single crystals with the formula (C70)x(C60)1-x(SnI4)2 (x = 0-1) are reported. C60, which is spherical, and C70, which is ellipsoidal, form a solid solution in these crystals, and the cubic lattice parameter of the chiral phase linearly increases as x grows from 0 to 1 in accordance with Vegard’s law. Our results demonstrate that nonspherical particles and polydispersity are not an impediment to the growth of chiral crystals from high-symmetry achiral precursors, providing a route to assemble achiral particles including colloidal nanocrystals and engineered nanostructures into chiral materials without the need to use external templates.

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Self-assembly of lattices with high structural complexity from a geometrically simple molecule

Science ◽

10.1126/science.aat6394 ◽

2018 ◽

Vol 361 (6408) ◽

pp. 1242-1246 ◽

Cited By ~ 39

Author(s):

Hiroshi Yamagishi ◽

Hiroshi Sato ◽

Akihiro Hori ◽

Yohei Sato ◽

Ryotaro Matsuda ◽

...

Keyword(s):

Porous Structure ◽

Self Assembly ◽

Molecular Crystal ◽

Structural Complexity ◽

High Symmetry ◽

Thermal Breakdown ◽

Wall Formation ◽

Simple Molecule ◽

Porous Crystal ◽

Wall Components

Here we report an anomalous porous molecular crystal built of C–H···N-bonded double-layered roof-floor components and wall components of a segregatively interdigitated architecture. This complicated porous structure consists of only one type of fully aromatic multijoint molecule carrying three identical dipyridylphenyl wedges. Despite its high symmetry, this molecule accomplishes difficult tasks by using two of its three wedges for roof-floor formation and using its other wedge for wall formation. Although a C–H···N bond is extremely labile, the porous crystal maintains its porosity until thermal breakdown of the C–H···N bonds at 202°C occurs, affording a nonporous polymorph. Though this nonporous crystal survives even at 325°C, it can retrieve the parent porosity under acetonitrile vapor. These findings show how one can translate simplicity into ultrahigh complexity.

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Vertex-directed self-assembly of a high symmetry supermolecular building block using a custom-designed porphyrin

Chemical Science ◽

10.1039/c2sc20330h ◽

2012 ◽

Vol 3 (9) ◽

pp. 2823 ◽

Cited By ~ 83

Author(s):

Xi-Sen Wang ◽

Matthew Chrzanowski ◽

Wen-Yang Gao ◽

Lukasz Wojtas ◽

Yu-Sheng Chen ◽

...

Keyword(s):

Self Assembly ◽

Building Block ◽

High Symmetry

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High-Symmetry Coordination Cages via Self-Assembly

Accounts of Chemical Research ◽

10.1021/ar010142d ◽

2002 ◽

Vol 35 (11) ◽

pp. 972-983 ◽

Cited By ~ 1266

Author(s):

S. Russell Seidel ◽

Peter J. Stang

Keyword(s):

Self Assembly ◽

High Symmetry ◽

Coordination Cages

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Amino acid sequence controls the self-assembled superstructure morphology of N-acetylated tri-β3-peptides

Pure and Applied Chemistry ◽

10.1515/pac-2015-0108 ◽

2015 ◽

Vol 87 (9-10) ◽

pp. 1021-1028 ◽

Cited By ~ 15

Author(s):

Rania S. Seoudi ◽

Annette Dowd ◽

Mark Del Borgo ◽

Ketav Kulkarni ◽

Patrick Perlmutter ◽

...

Keyword(s):

Amino Acid ◽

Self Assembly ◽

Far Infrared ◽

High Symmetry ◽

Amino Acid Residues ◽

Cross Sectional ◽

Self Assembling ◽

Afm Imaging ◽

High Degree ◽

Degree Of Similarity

AbstractPeptides based on unnatural β3-amino acids offer a versatile platform for the design of self-assembling nanostructures due to the folding stability of the 14-helix and the high symmetry of the side chains inherent in this geometry. We have previously described that N-terminal acetylation (Ac-) forms a supramolecular self-assembly motif that allows β3-peptides to assemble head-to-tail into a helical nanorod which then further bundles into hierarchical superstructures. Here we investigate the effect of the topography of the 14-helical nanorod on lateral self-assembly. Specifically, we report on the variations in the superstructure of three isomeric peptides comprising the same three β3-amino acid residues: β3-leucine (L), β3-isoleucine (I) β3-alanine (A) to give peptides Ac-β3[LIA], Ac-β3[IAL] and Ac-β3[ALI]. AFM imaging shows markedly different superstructures for the three peptides. Well defined synchrotron far-infrared spectra reveal uniform geometries with a high degree of similarity between the isomeric peptides in the amide modes of the 400–650 wavenumber range. Far-IR also confirms that the C-terminal carboxyl group is free in the assemblies, thus it is solvated in the dispersant. Hence, the differences in the superstructures formed by the fibers are defined primarily by van der Waals energy minimization between the varied cross sectional morphologies of the core nanorods.

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A Chiral Van Der Waals Material Self-Assembled from the High Symmetry Molecules C60 and SnI4

10.26434/chemrxiv.12196788.v1 ◽

2020 ◽

Author(s):

Daniel B. Straus ◽

Robert J. Cava

Keyword(s):

Organic Synthesis ◽

Self Assembly ◽

Van Der Waals ◽

The Self ◽

High Symmetry ◽

Molecular Chirality ◽

Molecular Precursor ◽

Chiral Materials ◽

Self Assembled ◽

Chiral Centers

The design of new chiral materials usually requires stereoselective organic synthesis to create molecules with chiral centers. Less commonly, achiral molecules can self-assemble into chiral materials, despite the absence of intrinsic molecular chirality. Here, we demonstrate the assembly of high-symmetry molecules into a chiral van der Waals structure by synthesizing crystals of C60(SnI4)2 from icosahedral buckminsterfullerene (C60) and tetrahedral SnI4 molecules through spontaneous self-assembly. Our results represent the remarkable emergence of chirality from the self-assembly of two of the most highly symmetric molecules, demonstrating that almost any molecular precursor can be considered when designing chiral assemblies.

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Self-Assembly of a Chiral Cubic Three-Connected Net from the High Symmetry Molecules C60 and SnI4

10.26434/chemrxiv.12196788.v2 ◽

2020 ◽

Author(s):

Daniel B. Straus ◽

Robert J. Cava

Keyword(s):

Organic Synthesis ◽

Self Assembly ◽

Van Der Waals ◽

Van Der Waals Forces ◽

High Symmetry ◽

Molecular Chirality ◽

Chiral Materials ◽

Self Assembled ◽

Chiral Centers

The design of new chiral materials usually requires stereoselective organic synthesis to create molecules with chiral centers. Less commonly, achiral molecules can self-assemble into chiral materials, despite the absence of intrinsic molecular chirality. Here, we demonstrate the assembly of high-symmetry molecules into a chiral van der Waals structure by synthesizing crystals of C60(SnI4)2 from icosahedral buckminsterfullerene (C60) and tetrahedral SnI4 molecules through spontaneous self-assembly. The SnI4 tetrahedra template the Sn atoms into a chiral cubic three-connected net of the SrSi2 type that is held together by van der Waals forces. Our results represent the remarkable emergence of a self-assembled chiral material from two of the most highly symmetric molecules, demonstrating that almost any molecular, nanocrystalline, or engineered precursor can be considered when designing chiral assemblies.

Download Full-text