| Abstract
| - A synthetic approachnamely slippageto self-assembling[n]rotaxanes incorporating π-electrondeficientbipyridinium-based dumbbell-shaped components and π-electron-richhydroquinone- and/or dioxynaphthalene-basedmacrocyclic polyether components has been developed. The kineticsof rotaxane formation by the slipping procedurewere investigated by absorption UV−visible and 1H-NMRspectroscopies in a range of temperatures and solvents,varying systematically the size of both the stoppers and themacrocyclic components. As expected, the rateconstantsfor these processes are affected by the size complementarity betweenmacrocycles and stoppers. Furthermore, theenthalpic and entropic contributions to the free energies of activationassociated with the slippage and the effect ofsolvent polarity upon the outcome of these processes have beenevaluated. In addition, the spectroscopic andelectrochemical properties of some of the rotaxanes are presented anddiscussed with reference to the properties oftheir chromophoric and electroactive units.
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