762245-08-9Relevant academic research and scientific papers
1H NMR analysis of porphyrin-stoppered rotaxanes: Effect of the porphyrin substituents on the macrocycle
Ikeda, Taichi,Asakawa, Masumi,Shimizu, Toshiini
, p. 870 - 873 (2007/10/03)
Six kinds of porphyrin-stoppered rotaxanes were prepared by the combination of two threads (relatively longer and shorter) and three porphyrin rhodium chlorides having different substituents. The chemical shift changes in 1H NMR spectra, due to the anisotropic shielding effects by the aromatic rings, enabled us to estimate the molecular structure. In the cases of the rotaxanes with relatively shorter thread, the conformation of the macrocycle proved to be affected by the substituents in the terminal porphyrin. This result suggests a mechanical interaction between the macrocycle and terminal porphyrin. This result will lead to novel designing of the molecular devices that can regulate the rotational motion of the macrocycle by the terminal porphyrin or transmit the rotational motion from the macrocycle to the terminal porphyrin.
