The Slipping Approach to Self-Assembling [n]Rotaxanes
| Autor: | Oldrich Kocian, Vincenzo Balzani, Masumi Asakawa, Peter R. Ashton, Margherita Venturi, J. Fraser Stoddart, Maria Teresa Gandolfi, Martin Bělohradský, Roberto Ballardini, Françisco M. Raymo, Luca Prodi |
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| Rok vydání: | 1997 |
| Předmět: | |
| Zdroj: | Journal of the American Chemical Society. 119:302-310 |
| ISSN: | 1520-5126 0002-7863 |
| DOI: | 10.1021/ja961817o |
| Popis: | A synthetic approachnamely slippageto self-assembling [n]rotaxanes incorporating π-electron deficient bipyridinium-based dumbbell-shaped components and π-electron-rich hydroquinone- and/or dioxynaphthalene-based macrocyclic polyether components has been developed. The kinetics of rotaxane formation by the slipping procedure were investigated by absorption UV−visible and 1H-NMR spectroscopies in a range of temperatures and solvents, varying systematically the size of both the stoppers and the macrocyclic components. As expected, the rate constants for these processes are affected by the size complementarity between macrocycles and stoppers. Furthermore, the enthalpic and entropic contributions to the free energies of activation associated with the slippage and the effect of solvent polarity upon the outcome of these processes have been evaluated. In addition, the spectroscopic and electrochemical properties of some of the rotaxanes are presented and discussed with reference to the properties of their chrom... |
| Databáze: | OpenAIRE |
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