The role of covalent, coordinative, and supramolecular interactions utilized by chemists and biochemists, when they are assembling molecular knots and links, are presented. The Trefoil Knot comprises a simple overhand knot where the two ends have been connected and can exist in left-handed and right-handed forms. A molecular Trefoil Knot displays inherent topological chirality and any representation of its graph cannot be deformed in 3D space to its mirror image, and exists as two enantiomers. A significant increase in knot yields is achieved by replacing the polymethylene linker with a meta-phenylene bridge, a change of design that resulted in the quantitative assembly of the precursor double helical complex. Alkene metathesis is particularly suited to macrocyclizations involving Cu(I)-templated species as it is a thermodynamically controlled reaction. It also avoids the need for addition of destabilizing bases, such as NaH, which are required when alkylation is the final step in the reaction sequence.
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