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Updated: May 11, 2026

Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Using "threading followed by shrinking" to synthesize highly stable dialkylammonium-ion-based rotaxanes
Liang-Yun Wang1, Jia-Ling Ko, Chien-Chen Lai
1Department of Chemistry and Center for Emerging Material and Advanced Devices, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, Taiwan 10617, R.O.C.
Abstract:
Herein, we report a "threading followed by shrinking" approach for the synthesis of rotaxanes by using an "oxygen-deficient" macrocycle that contained two arylmethyl sulfone units and the dumbbell-shaped salt bis(3,5-dimethylbenzyl)ammonium tetrakis(3,5-trifluoromethylphenyl)borate as the host and guest components, respectively. The extrusion of SO2 from both of the arylmethyl sulfone units of the macrocyclic component in the corresponding [2]pseudorotaxane resulted in a [2]rotaxane that was sufficiently stable to maintain its molecular integrity in CD3 SOCD3 at 393 K for at least 5 h.
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