https://doi.org/10.1351/goldbook.13965
Molecule that has at least one ring (cycle) large enough to allow it to be threaded onto a linear subchain of another molecule.
Notes:
- To thread a simple hydrocarbon chain such as a polyethylene chain, at least a 24-membered ring is needed.
- In a macromolecular rotaxane, a macrocyclic component can be a discrete macrocyclic molecule or a macromolecule that includes one or more threadable ring(s). Examples and structure representations of both are shown:
- The literature on rotaxanes frequently cites the word "macrocycle" as a contraction of (and an abbreviation for) macrocyclic component. A use of the word "macrocycle" in rotaxane terminology is incompatible with the IUPAC definition of a macrocycle, which is "a cyclic macromolecule or a macromolecular cyclic portion of a macromolecule": Such a macrocycle is virtually never used as a macrocyclic component in a rotaxane assembly. Therefore, since the term "macrocycle" is ambiguous, its use should be avoided in the macromolecular rotaxane literature.
See also: threading component