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Cooperative Effects in Switchable Catalysis: Enhancing Double-Click Reaction Yield of Symmetrical Rotaxanes.

ABSTRACT: Reversible switching between the closed cyclic dimeric assembly [Cu₂ (1)₂ ]²⁺ (OFF state) and the extended dimeric homoleptic complex [FeCu₂ (1)₂ ]⁴⁺ (ON State) by addition/removal of Fe²⁺ triggered catalysis of a double-click reaction and high yield preparation of [2]rotaxanes. Mechanistic and computational studies provide valuable general insight for double-click strategies by revealing cooperative effects in the second cycloaddition step due to a distance-tolerant preorganization of the first-click product by the two copper(I)-loaded phenanthroline subunits of [FeCu₂ (1)₂ ]⁴⁺ .

SUBMITTER: Ghosh A

PROVIDER: S-EPMC8457069 | biostudies-literature |

REPOSITORIES: biostudies-literature

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