A molecular endless (74) knot

@article{Leigh2020AME,
  title={A molecular endless (74) knot},
  author={David A. Leigh and Jonathan J. Danon and Stephen D. P. Fielden and Jean-François Lemonnier and George F. S. Whitehead and Steffen L. Woltering},
  journal={Nature Chemistry},
  year={2020},
  volume={13},
  pages={117 - 122}
}
Current strategies for the synthesis of molecular knots focus on twisting, folding and/or threading molecular building blocks. Here we report that Zn(ii) or Fe(ii) ions can be used to weave ligand strands to form a woven 3 × 3 molecular grid. We found that the process requires tetrafluoroborate anions to template the assembly of the interwoven grid by binding within the square cavities formed between the metal-coordinated criss-crossed ligands. The strand ends of the grid can subsequently be… 
28 Citations

Vernier template synthesis of molecular knots

Molecular knots are often prepared using metal helicates to cross the strands. We found that coordinatively mismatching oligodentate ligands and metal ions provides a more effective way to synthesize

Social Self-Sorting Synthesis of Molecular Knots.

We report the synthesis of molecular prime and composite knots by social self-sorting of 2,6-pyridinedicarboxamide (pdc) ligands of differing topicity and stereochemistry. Upon mixing achiral

Knotting matters: orderly molecular entanglements.

Entangling strands in a well-ordered manner can produce useful effects, from shoelaces and fishing nets to brown paper packages tied up with strings. At the nanoscale, non-crystalline polymer chains

Circuit Topology for Bottom-Up Engineering of Molecular Knots

TLDR
This conceptual paper systematically analyze the circuit topology approach to a description of linear chain entanglement, utilizing a bottom-up approach and believes that such a detailed, bottom- up understanding of the structure of molecular knots should be beneficial for molecular engineering.

How Cooperatively Folding Are Homopolymer Molecular Knots?

Detailed thermodynamic analysis of complex systems with multiple stable configurational states allows for insight into the cooperativity of each individual transition. In this work we derive a heat

Molecular weaving

Historically, the interlacing of strands at the molecular level has mainly been limited to coordination polymers and DNA. Despite being proposed on a number of occasions, the direct, bottom-up

Discrete self-assembled metallo-foldamers with heteroleptic sequence specificity.

TLDR
Here is presented an approach integrating palladium(II) metal ions into the sequence itself, with fidelity maintained through use of complementary pairings of ligand arrangements at the metal centre, using sites of different denticity and/or hydrogen bonding capability.

Selective construction and stability studies of a molecular trefoil knot and Solomon link.

TLDR
Two novel compounds, a molecular trefoil knot and a Solomon link, were constructed successfully through the cooperation of multiple π-π stacking interactions, which open the door to the further development of smart materials, which will push the advancement of rational design of biomaterials.

Dimeric and Trimeric Catenation of Giant Chiral [8+12] Imine Cubes Driven by Weak Supramolecular Interactions

Mechanically interlocked structures, such as catenanes or rotaxanes are fascinating synthetic targets and are the basis of molecular switches and machines. Today, the vast majority of catenated

Metal-Peptide Nonafoil Knots and Decafoil Supercoils.

TLDR
The efficient entanglement of metal-peptide strands and the wide scope for design of the amino acid side chains in these ligands enabled the construction ofMetal- peptide 91 torus knots and 1012 torus links, which resulted in an infinite toroidal supercoil nanostructure.

References

SHOWING 1-10 OF 54 REFERENCES

A synthetic molecular pentafoil knot.

TLDR
The synthesis of the most complex non-DNA molecular knot prepared to date, which features an exceptional number of different design elements within the context of directing the formation of (supra)molecular species, is reported on.

Discovery of an Organic Trefoil Knot

TLDR
Near-quantitative self-assembly of a trefoil knot from a naphthalenediimide-based aqueous disulfide dynamic combinatorial library is reported, demonstrating that the hydrophobic effect provides a powerful strategy to direct the synthesis of entwined architectures.

Tying different knots in a molecular strand

TLDR
This work shows that interspersing coordination sites for different metal ions within an artificial molecular strand enables it to be tied into multiple knots, and finds that the metal-ion-induced folding can proceed with stereoinduction.

A Strategy to Synthesize Molecular Knots and Links Using the Hydrophobic Effect.

TLDR
This work designed an aqueous dynamic combinatorial system that can generate knots and links that uses the hydrophobic effect to drive the formation of complex interlocked structures in water and illustrates the validity of this concept with the syntheses of a Hopf link, a Solomon link, and a trefoil knot.

Synthesis of a molecular trefoil knot by folding and closing on an octahedral coordination template.

TLDR
A synthetic strategy for the preparation of a molecular trefoil knot from a flexible bipyridine oligomer and a zinc(II) octahedral coordination template is reported.

Coordination-Driven Self-Assembly of a Molecular Knot Comprising Sixteen Crossings.

TLDR
This study reports the coordination-driven [8+8] self-assembly of a higher-generation molecular knot comprising as many as sixteen crossings and its solid-state X-ray crystal structure and multinuclear 2D NMR findings confirmed its architecture and topology.

Braiding a molecular knot with eight crossings

TLDR
It is found that it is possible to assemble four building blocks into three braided ligand strands in a molecular 819 knot featuring eight nonalternating crossings in a 192-atom closed loop ~20 nanometers in length.

A triaxial supramolecular weave

TLDR
An extended triaxial supramolecular weave that consists of self-assembled organic threads that was found to be more robust than non-woven self-assemblies of the same building block and able to host iridium nanoparticles, which may be of interest for practical applications.

Template synthesis of molecular knots.

TLDR
This tutorial review outlines the different template strategies that chemists have employed to synthesise knotted molecular topologies, including the active metal template strategy in which metal ions both organise crossing points and catalyse the bond forming reactions that close the loop to form the topologically complex product.
...