Cyclophane template-directed synthesis

Fig. 5 Distribution scheme for template-directed synthesis of cyclophane 104 +. 60...

Scheme 10.3 Template-directed synthesis of a tetracationic cyclophane by Stoddart and coworkers.

Brown, C.L., Philp, D., and Stoddart, J.F. (1991) The template directed synthesis of a rigid tetracationic cyclophane receptor, Synlett, 462-464. 

Although many synthetic routes have been adopted for the preparation of azacycloalkanes and -cyclophanes, the vast majority of cyclization procedures can be grouped into two major categories (i) direct synthesis by conventional organic reactions and (ii) metal ion-promoted (template) reactions. 

Template effects have been used in rotaxane synthesis to direct threading of the axle through the wheel. Since macrocycHc compounds such as cyclodextrins, crown ethers, cyclophanes, and cucurbiturils form stable complexes with specific guest molecules, they have been widely used in the templated synthesis of rotax-anes as ring (wheel) components. Here, we briefly discuss macrocycles used in the synthesis of rotaxane dendrimers and their important features. 

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