Stopper Frechet type

Fig.1. Rotaxane dendrimers from crown ether type macrocycle ring, bipyridinimn derivatives rod component and Frechet-type dendron stoppers...

Fig. 2. Rotaxane dendrimers from isophthalamide [2]rotaxane-core and Frechet-type den-dron stoppers...

Stoddart and co-workers have made use of Frechet-type dendrons as dendritic stoppers for self-assembled [n]rotaxanes [65]. The solubility enhancement that results from incorporating dendritic wedges at the termini facilitated the purification of these materials by column chromatography despite the polycationic nature of their bipyridinium backbone. Again, the dendritic wedges did not alter the electrochemical characteristics of the viologen subunits. Flowever, the enhanced solubility resulting from the presence of the dendritic components en-... 

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