Cationic and Neutral Rotaxanes Having Different Functional Groups in the Axle Molecule and Their Coordination to PtII

• Main Authors: Yu, Gilbert U, Suzaki, Yuji, Osakada, Kohtaro
• Format: text
• Published: Archīum Ateneo 2016
• Subjects: Chemistry
• Online Access: https://archium.ateneo.edu/chemistry-faculty-pubs/10; https://onlinelibrary.wiley.com/doi/full/10.1002/asia.201601554
• Institution: Ateneo De Manila University

Dibenzo[24]crown‐8 (DB24C8) forms rotaxanes with a linear molecule having a dialkylammonium group and a triazole group as well as with the acetylation product of a cationic axle molecule. The former cationic rotaxane is stabilized by multiple intermolecular hydrogen bonds between the NH2+ and oxyethylene groups. The neutral rotaxane contains the macrocycle in the vicinity of the terminal aryl group. The co‐conformation of both the cationic and neutral rotaxanes can be fixed by coordination of the triazole group of the axle molecule to PtCl2(dmso)2. A 1H NMR spectroscopic study on the thermodynamics of the Pt coordination revealed a larger association constant for the rotaxanes than for the corresponding axle molecules and a larger value for the neutral rotaxane than for the cationic rotaxane.