Template Effects for the Syntheses of Rotaxanes, Catenanes, and Knots

Template Effects for the Syntheses of Rotaxanes, Catenanes, and Knots 

FORMATION OF A ROTAXANE IS POSSIBLE BY ATTACHING STOPPERS TO THE TWO FREE PYRIDINES IN THE DONOR/ACCEPTOR COMPLEX. 

However, directionality of individual non-covalent interactions is not always needed and even non-directional forces such as the hydrophobic effect can be utilized for the preparation of interlocked structures. Cyclodextrins may serve as a first example. They are macrocycles built from a-glycosidic D-glucose subunits. While their hydrophilic, OH group-decorated surface makes them water soluble, they bear a lipophilic 

UNPOLAR AXLE CENTERPIECE INTO THE CAVITY OF (5-CYCLODEXTRIN 9. THE BIS-(ETHYLENE DIAMINE) CHLORO COBALT(II) STOPPERS ARE SUFFICIENTLY LARGE AND POLAR TO PREVENT DESLIPPING OF THE AXLE. 

DITOPIC LIGAND (10) AND PALLADIUM OR PLATINUM COMPLEXES 11a,b. THE COORDINATION GEOMETRY AT THE METAL CENTERS AND THE RIGIDITY OF THE LIGANDS DETERMINE THE FINAL STRUCTURE. 

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