Molecular knot

File:Molecular Knot RecTravChimPays-Bas 427 1993 commons.jpg

Crystal structure of a molecular trefoil knot with two copper(I) templating ions bound within it reported by Sauvage and coworkers

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Crystal structure of a molecular trefoil knot reported by Vögtle and coworkers in the Angew. Chem. Int. Edit., 2000, 1616-1618.

In chemistry, a molecular knot, or knotane, is a mechanically-interlocked molecular architecture that is analogous to a macroscopic knot. A molecular knot in a trefoil knot configuration is chiral, having at least two enantiomers. Examples of naturally formed knotanes are DNA and certain proteins. Lactoferrin has an unusual biochemical reactivity compared to its linear analogue. Other synthetic molecular knots have a distinct globular shape and nanometer sized dimensions that make them potential building blocks in nanotechnology. The first knot was synthesised by Sauvage in 1989.

The term knotane was coined by Fritz Vögtle et al. in Angewandte Chemie International Edition in 2000 by analogy with rotaxane and catenane. The term however has yet to be adopted by IUPAC.

Several synthetic knotanes have been reported. A pentafoil knot has also been reported.

See also

• Macrocycles
• Supramolecular chemistry