Catenane template

Figure 6. Synthesis of a [2]catenane templated by donor-acceptor and hydrogen bond interactions [23].

In the case of catenanes, the most rationale synthetic strategy is the clipping of a macrocycle onto a preformed one (Fig. 8). A double-clipping procedure can also be used [46]. Figure 9 shows the synthesis of a catenane templated by electron donor/acceptor interactions [45]. Reaction of a... 

SYNTHESIS OF INTERLOCKING RINGS USING TWO DIFFERENT TRANSITION METALS AS TEMPLATING AND CONNECTING CENTERS RuCu(20.4) -", RuZn(20.4), AND RuAg(20.4) CATENANES TEMPLATE SYNTHESIS OF A 5-COORDINATE ZINC(1I) CATENANE,... 

The unlimited possibilities of designing multidentate and multitopic ligands that take advantage of the coordination geometry of specific metal ions to assemble a variety of supramolecular multinuclear architectures are far beyond the scope of this chapter, and the reader will find inspiring and fascinating examples in several reviews, as well as in other chapters of this work (see Self-Assembled Links Catenanes, Templated Synthesis of... 

Template synthesis and chirality of catenanes, rotaxanes, and pretzelanes including N-macroheterocyclic lactams and related compounds as structure components 99PAC247. 

Nonionic template synthesis of amide-linked catenanes and rotaxanes with macroheterocyclic fragments 97AG(E)930. 

The template-directed preparation of cycloi is(paraquat-4,4 -biphenylene (a molecular square ) has been achieved the use of a macrocyclic hydroquinone-based polyether template incorporating an ester moiety in one polyether chain afforded a 1 1 mixture of two topologically stereoisomeric [3]catenanes <96CEJ877>. 

Schalley CA, WeUandt T, Briiggemann J,V6gtle F (2004) Hydrogen-Bond-Mediated Template Synthesis of Rotaxanes, Catenanes, and Knotanes. 248 141-200 Scheer M,see Balazs G (2003) 232 1-23... 

Sauvage, J.-P. Dietrich-Buchecker, C. O. Chambron, J.-C. Transition metals as assembling and templating species synthesis of catenanes and molecular knots. In Comprehensive Supramolecular Chemistry, Sauvage, J.-P. Hosseini, M.W., Ed., Publisher Elsevier, Oxford, UK 1996 Vol. 2, p 43. 

Other supramolecular structures such as catenanes and rotaxanes can be formed using zinc as a template ion for example, a benzylic imine catenate formed by Leigh et a/.288 The reversible five-component assembly of a [2]catenane from a chiral metallomacrocycle and a dinaphtho-crown ether has been achieved. Zinc is used as the metal component and drives assembly via the coordination to a bipyridyl unit 7r interactions between the aromatic components are also... 

The group of Sauvage et al. [121] produced various [2]catenanes by using transition metal complexes as templates. Figure 41 illustrates one of their... 

A useful summary of the various and numerous types of rotaxanes, catenanes, and knots can be found in a review of template routes to interlocked molecular structures 468). Inorganic chemistry is centrally involved in the templating involved in self-assembly and in controlled synthesis of such species. 

Pseudorotaxanes are precursors of both rotaxanes and catenanes they consist of a guest molecule threaded through a macrocyclic host. Stoppering both ends of the threaded molecule gives a rotaxane, cycliza-tion of the thread gives a catenane. Pseudorotaxane formation may occur by spontaneous self-assembly, or may be template-controlled. Anion size can be of paramount importance for such templates - Cl- is effective, Br, I- less good, and PFe ineffective when the recognition motif demands a small template (454). 

R. Jager, F. Vogtle, A New Synthetic Strategy towards Molecules with Mechanical Bonds Nonionic Template Synthesis of Amide-Linked Catenanes and Rotaxanes , Angew. Chem Int. Ed. Engl. 1997,36,930-944. 

Keywords Templates Hydrogen Bonding Self-assembly Cages Macrocycles Catenanes ... 

In the early 1990s Hunter [49] and Vogtle [50,51] discovered independently the possibility of using hydrogen bonding interactions displayed by amide groups to template the formation of [2 ] catenanes. While studying the reaction between the... 

Scheme 8 Hunter and Vogtle reported independently the templated synthesis of catenanes 12 and 14... 

Scheme 10 Leigh has reported the hydrogen-bonding templated synthesis of catenane 15...

Scheme 11 Hydrogen-bonding templated preparation of catenane 18 under thermodynamic control...

This elegant synthesis has demonstrated the possibility of using a hydrogen bond-acceptor template to prepare template-free interlocked species (in a similar fashion to Sauvage s catenanes syntheses which make use of transition metals as templates). 

Schalley CA, Weilandt T, Briiggemann J, Vogtle F (2004) Hydrogen-bond-mediated template synthesis of rotaxanes, catenanes, and knotanes. Top Curr Chem 248 141-200... 

Figure 5.8 A single enchainment stereo isomer is obtained in the acetylcholine templated synthesis of a [2] catenane.

The iron(II) complex of the Schiff base-diimine (121) is mentioned briefly in a review more concerned with Cu" "-diimine complexes leading to helicates and catenanes—but which is also concerned with moving from tetrahedral Cu+ to octahedral metal centers as templates. 

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