After characterising the shape of one of these catalysts, the focus of his research changed to that recognised by the 2016 Nobel Prize in chemistry: synthesising molecules with interlocking rings and knots. (lindau-nobel.org)
In 1961, H. L. Frisch and E. Wasserman, at Bell Labs, connected topology to the chemical world, publishing ideas to synthesise molecules with interlocking rings and knots. (lindau-nobel.org)
Over the next decade, Sauvage and his group synthesised and characterised molecules with more complex topologies, including a doubly-interlocking catenane and molecular trefoil knot with three loops and three crossings. (lindau-nobel.org)
Having previously bent molecules into shapes such as a Star of David , the team also holds the Guinness record for creating the world's tightest knot . (chemistryworld.com)
Stitching together the ends of the grid or helicate molecules then makes the knot. (chemistryworld.com)
Unlike ordinary chemical bonds, the molecules in catenanes are linked like a chain, and so the links can move relative to each other. (nanowerk.com)
Synthesis4
In 1983, he, along with Christiane Dietrich-Buchecker and J.P. Kintzinger, synthesised a [2]catenane in two steps, compared to the 15 steps needed in the previous synthesis. (lindau-nobel.org)
Although the paper remains one of the few French papers of his career, the concept of templating catenane synthesis has become a standard method in the field. (lindau-nobel.org)
His doctoral work focused on the dynamic combinatorial synthesis of unusual donor-acceptor catenanes. (universityofgalway.ie)
This work, published in Nature ( 'Self-assembled poly-catenanes from supramolecular toroidal building blocks' ), reports the first template-free synthesis of nano-poly[n]catenanes via molecular self-assembly. (nanowerk.com)
Molecular knot2
These approaches have been particularly successful in preparing unpredictable Catenanes and other complex macrocycles including a molecular knot. (wikipedia.org)
Now, they have added four more entries to the molecular knot lexicon: two knots comprising two and three linked figure-of-eights, respectively, a granny knot and a three-trefoil tangle. (chemistryworld.com)
Sequentially2
Schill and Lüttringhaus synthesised the first molecule with two interlocking rings, in an elegant, but lengthy, process that built each ring of the [2]catenane sequentially. (lindau-nobel.org)
Informed by the step-wise nature of the formation mechanism, they added monomers sequentially, and were thereby able to create poly[n]catenanes with up to 22 rings. (nanowerk.com)
Crossings2
Mathematicians classify topological knots as identical if they have the same number of loops and crossings, even if their shapes appear drastically different. (lindau-nobel.org)
Writhe is a measure of how coiled a knot is by counting the number of its 'over' versus 'under' crossings. (chemistryworld.com)
Structures2
Topological knots can also be found in biological structures. (lindau-nobel.org)
By altering self-assembly conditions, the group were able to create intricate structures, including a nano-[5]catenane with interlocked rings in a linear arrangement, which has been named "nanolympiadane" in homage to the [5]catenane system "olympiadane" first reported by Fraser Stoddart and colleagues in 1994, and the well-known symbol of the Olympic games. (nanowerk.com)
Assemblies1
The knot is so tangled that Leigh's team needed to protein crystallography methods - which can deal with complex assemblies - to resolve its x-ray structure. (chemistryworld.com)
Complex1
This paves the way to create even more complex geometric compounds such as 'rotaxane' and 'trefoil knot' at a similar scale. (nanowerk.com)
Route1
About twenty years later, Sauvage recognised that his copper catalyst pre-assembled the interlocking portion of the catenane, providing a fast and efficient route to the simplest molecular chain. (lindau-nobel.org)
Applications2
While the two knots don't have an immediate practical use, applications are starting to emerge. (chemistryworld.com)
3) developing applications using molecular knots at the interface with other disciplines. (universityofgalway.ie)
Rings1
Sauvage realised that closing each crescent to form a loop would create a molecule with two interlocking rings, called a [2]catenane. (lindau-nobel.org)
Years1
A molecular trefoil knot Leigh's team created a few years ago catalyses enantioselective reactions. (chemistryworld.com)
Chain1
The triple trefoil is made of a single, 324-atom-long chain. (chemistryworld.com)
Molecular6
These approaches have been particularly successful in preparing unpredictable Catenanes and other complex macrocycles including a molecular knot. (wikipedia.org)
Chemistry with a super-twist: A molecular trefoil knot, part 1. (imperial.ac.uk)
It is a molecular trefoil, constructed by joining 15 pyrrole units together into a ring with appropriate linkers and in effect tying a knot in that ring. (imperial.ac.uk)
A molecular trefoil knot, shown with a Mg at the centre. (imperial.ac.uk)
Accordingly, we decided to apply the know-how we had gained from the tying of molecular knots 12,13 to the weaving of polymer chains. (rotaxane.net)
We recently found 14 that the crystal structure of a 3×3 molecular grid we were developing for a molecular 7 4 (endless) knot synthesis (Figure 1) had a layered structure with all of the grid ligand strands running parallel or orthogonal to the other strands in the same layer. (rotaxane.net)
Mathematics1
The trefoil knot is a most interesting object in a branch of mathematics called knot theory , and it is also related to another fascinating object, the Möbius band . (imperial.ac.uk)
Theory2
The questions vary from topological graph theory related to DNA strand routing a three-dimensional mesh, to questions in knot theory related to structural embeddings in 3D, to algebraic descriptions related to Jones monoids associated with DNA origami. (brown.edu)
I will describe several ways in which tools from reinforcement learning and natural language processing can help with problems in knot theory and low-dimensional topology, including hard challenges such as the smooth Poincare conjecture in dimension 4 and its variants. (brown.edu)