Catenane template-directed synthesis

As already said, catenanes are minimally composed of two interlocked rings. If it is arranged during the template-directed synthesis to have two identical units, that is, recognition sites, located within two different macrocycles, then the resulting... 

Figure 15. The template-directed synthesis of the [2]catenanes 32-4PF6-384PF6. The insets show (i) the intermediate [2]pseudorotaxane formed during the course of catenane formation and (ii) the solid-state structure of the [2]catenane 324+.

Figure 28. The hydrogen-bonding template-directed synthesis of the [2]catenane 87.

Raymo, F.M., Stoddart, J.F. Organic Template Directed Synthesis of Catenanes, Rotaxanes and Knots. In ref. 4b, p.143. 

The -electron-deficient pyridinium ring has played an important role in template-directed synthesis in which the interaction of a -electron acceptor and a -electron donor facilitate self-assembly. This has led to the construction of a variety of supramolecular assemblies including catenanes (linked rings) and rotaxanes (wheel and axle) . 

In 1989, following extensive preparatory work discussed, the template-directed synthesis of the positively charged [2]-catenane 5 was reported by the Stoddart group (Figure 5.2). Only mild conditions were required, with the crystalline catenane... 

Figure 5.17 The multistep template-directed synthesis of the high-order catenanes...

Stoddart and co-workers transferred the strategy of template-directed synthesis to the formation of the first molecular system consisting of five interlocked rings in a linear array (Structure 51). They suggested that this [5]catenane should be called olympiadane [64]. Recently they reported the self-assembly of a new type of rotaxane, in which three side chains are linked directly to a single central core, producing a dendritic-type structure [65]. 

Figure 3-7 Template-directed synthesis of the cyclodextrin-containing catenanes 25-28.

Figure 25 (a) Synthesis of mixed benzylic amide esto catenane 93 by template-directed synthesis and (b) magic-ring catenane 95... 

Figure 11 The donor/acceptor template-directed synthesis of the [2]catenanes 40 and 41 and their conversion into the poly[2]catenanes 42 and 44, respectively.

Griffiths, K. E. and Stoddart, J. F. Template-directed synthesis of donor/acceptor [2]catenanes and [2] rotaxanes. PureAppl. Chem. 80, 485-506, 2008. 

The use of metal coordination in the template-directed synthesis of knots and links is one of the earliest successful strategies employed by chemists. The first example of metal-templated synthesis of a [2]catenane was reported in Strasbourg by Sauvage et al. who first used the method to assemble two phenanthroline-based strands around a tetrahedral copper(I) cation (Scheme 17.1). 

Scheme 74,72 Template-directed synthesis of the first [2]catenane 42" prepared using click chemistry...

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