An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract The synthesis of amide‐based symmetrical rotaxanes 2a , b bearing porphyrin blocking groups is firstly described. These compounds can be obtained by a one‐step one‐pot reaction only if the macromonocyclic host template complementary to the threading guest is found. The symmetry of the axle is removed by introducing an unsymmetrical central part, leading to the formation of rotaxane 2c . Different blocking groups were used to obtain the non‐symmetrical rotaxane 3a . The bis‐Zn 2+ complex 10a of the rotaxane 2a was isolated. A nonionic supramolecular complex 7 was assumed as threaded intermediate, which was blocked by reaction with the stopper components. The amide‐type rotaxane system thus proved to be variable with respect to all its parts including stopper components of different reactivity, bulkiness and supramolecular functionality.
Abstract New catenanes of the amide‐linked type, such as 11 with one macrocycle containing two (CH 2 ) 12 chains are synthesized from long‐chain alkanediamines in yields of up to 21%. Consequently, the preorganization afforded by fixed and angular building units – so far considered essential – proves not to be necessary. The new sulfonamide catenanes exhibit high conformational flexibility. However, the circumrotation of one of the macrocycles can be hindered by substitution with bipyridine units at the sulfonamide nitrogen.
