Host–guest interactions template: the synthesis of a [3]catenane
作者:Amy L. Hubbard、Gregory J. E. Davidson、Roopa H. Patel、James A. Wisner、Stephen J. Loeb
DOI:10.1039/b312449e
日期:——
Formation of a [3]catenane containing dibenzo-24-crown ether wheels and a large dipyridiniumethane ring is templated by formation of a host-guest adduct between the [3]catenane and the external crown ether.
Iron(ii) complexes utilising terpyridine containing [2]rotaxanes as ligands
作者:Gregory J. E. Davidson、Stephen J. Loeb
DOI:10.1039/b308553h
日期:——
A terpyridine chelating group is incorporated into a cationic (dipyridinium)ethane axle and self-assembly synthesis used to create three [2]rotaxanes utilising 24-membered crown ether wheels: 24-crown-8, dibenzo-24-crown-8 and dinaphtho-24-crown-8 ether. The resulting [2]rotaxanes are characterised by 1H NMR spectroscopy, X-ray crystallography and mass spectrometry. The ability of these rotaxanes to
Rotaxanes Based on the 1,2-Bis(pyridinio)ethane-24-Crown-8 Templating Motif
作者:Darren J. Mercer、Sarah J. Vella、Lianne Guertin、Natalie D. Suhan、Jorge Tiburcio、V. Nicholas Vukotic、James A. Wisner、Stephen J. Loeb
DOI:10.1002/ejoc.201001616
日期:2011.3
interaction between 1,2-bis(pyridinio)-ethane axles and 24-membered crown ether wheels provides a template for the formation of interpenetrated [2]pseudorotaxanes. The preformed [2]pseudorotaxanes can then be kinetically trapped to produce permanently interlocked [2]rotaxanes by stoppering with bulky groups that prevent the unthreading of the resulting dumbbell from the wheel. Six [2]rotaxanes were created
A versatile template for the formation of [2]pseudorotaxanes. 1,2-Bis(pyridinium)ethane axles and 24-crown-8 ether wheels
作者:Stephen J. Loeb、Jorge Tiburcio、Sarah J. Vella、James A. Wisner
DOI:10.1039/b514528g
日期:——
Linear 1,2-bis(pyridinium)ethane ‘axles’ and macrocyclic 24-membered crown ether ‘wheels’ (24C8, DB24C8 and DN24C8) combine to form [2]pseudorotaxanes. These interpenetrated adducts are held together by N+⋯O ion-dipole interactions, a series of C–H⋯O hydrogen bonds and π-stacking between electron-poor pyridinium rings of the axle and electron-rich catechol rings of the wheel. 1H NMR spectroscopy was used to identify the structural details of the interaction and to determine the thermodynamics of the binding process in solution. Analysis of nine of these adducts by single crystal X-ray crystallography allowed a detailed study of the non-covalent interactions in the solid state. A wide variety of structural changes could be made to the system. The versatility and potential of the template for the construction of permanently interlocked structures such as rotaxanes and catenanes is discussed.
Electrochemical properties of 3,5-diphenylaniline units encapsulated within a crown ether. Effects of the macrocycle’s aromatic functionality and ring size
component and crownethers as the macrocyclic component, prepared through imine formation and hydrogen bond—guided self-assembly. Electrochemical studies of these [2]rotaxanes revealed that the oxidation potential of the aniline moiety when positioned within the cavity of a crownether was shifted negatively relative to that of the corresponding dumbbell-shaped compound, and that a crownether possessing