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Updated: Jun 21, 2025
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Urea-Based [2]Rotaxanes as Effective Phase-Transfer Organocatalysts: Hydrogen-Bonding Cooperative Activation Enabled
Julio Puigcerver1, Jose M Zamora-Gallego1, Marta Marin-Luna1
1Departamento de Quimica Organica, Facultad de Quimica, Regional Campus of International Excellence "Campus Mare Nostrum", Universidad de Murcia, E-30100 Murcia, Spain.
Abstract:
We finely designed a set of [2]rotaxanes with urea threads and tested them as hydrogen-bonding phase-transfer catalysts in two different nucleophilic substitutions requiring the activation of the reactant fluoride anion. The [2]rotaxane bearing a fluorinated macrocycle and a fluorine-containing urea thread displayed significantly enhanced catalytic activity in comparison with the combination of both noninterlocked components. This fact highlights the notably beneficial role of the mechanical bond, cooperatively activating the processes through hydrogen-bonding interactions.
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