= Solution
\b[The cation acts as a noncovalent template.] Coordination to the ether oxygens folds the open chain into conformations with its two alkene ends close together. This increases their effective local concentration and reduces the conformational search needed for <ring-closing metathesis>. The bound cyclic product is also stabilized relative to unbound alternatives, which can favour it in a reversible reaction network.
A well-matched ion therefore suppresses competing intermolecular connections and increases the isolated or analytical macrocycle yield. It need not become covalently incorporated into Z; it can be removed by changing the binding conditions during work-up. Nor is it necessarily the metathesis catalyst: the ruthenium complex performs bond reorganization, whereas the cation primarily changes preorganization and relative stability. A yield increase alone does not separate a kinetic templating effect from a thermodynamic one, and both can contribute.
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