A Musclelike (2)Rotaxane: Synthesis, Performance, and Molecular Dynamics Simulations
2014 (English)In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 79, no 15, 6996-7004 p.Article in journal (Refereed) Published
A novel bistable symmetric (2)rotaxane was prepared by a threading-followed-by-stoppering strategy and characterized with H-1, C-13, and 2D ROESY NMR spectroscopy and HR-ESI spectrometry. The symmetric  (2)rotaxane system consists of an anthracene-based bis(crown ether) as macrocycles, and each of the two dibenzocrown-8 (DB24C8) rings is threaded by the pendant substituents a symmetrically substituted central rotatable ferrocene subunit that possesses two distinguishable recognition sites for the DB24C8 ring: namely, a dibenzylammonium site and an N-methyltriazolium site. The uniform shuttling motion of the thread relative to the two DB24C8 rings in (2)rotaxane can be driven by external acid base stimuli, which was evidenced by H-1 and 2D ROESY NMR spectroscopy. Furthermore, molecular dynamics simulations of the (2)rotaxane were carried out both in protonated (stretched) and in neutral (contracted) forms. The calculated percentage change in molecular length of the (2)rotaxane between the two end-capping bis(methoxyl)phenyl groups is about 48% in the two different states (in acetone), which is much larger than the percentage change (similar to 27%) in human muscle. Moreover, in the two states, the C*-Cp-Cp-C* dihedral angles are computed as -177 degrees in the stretched state and -112 degrees in the contracted state, indicating a correlation between the translational and rotational motions of the (2)rotaxane.
Place, publisher, year, edition, pages
2014. Vol. 79, no 15, 6996-7004 p.
IdentifiersURN: urn:nbn:se:kth:diva-150527DOI: 10.1021/jo501127hISI: 000339983300022ScopusID: 2-s2.0-84905383823OAI: oai:DiVA.org:kth-150527DiVA: diva2:746294
QC 201409122014-09-122014-09-052014-09-12Bibliographically approved