Guest-templated synthesis

Guest-Templated Synthesis of a Kinetically Stable M6L4 Cage... 

Ibukuro, F. Kusukawa. T. Fujita, M.A. Thermally switchable molecular lock. Guest-templated synthesis of a kinetically stable nanosized cage. J. Am. Chem. Soc. 1998, 120. 8561-8562. 

The verdazyl tris-pyridyl radical syntone 257 has been used in [44] for the guest-templated synthesis of a host-guest 1 1 complex of TP... 

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. 

Among various preparation techniques of metal/alloy particles on the nanometre scale, the templating synthesis using microporous materials as microreactors is one of the promising methods [7, 10, 11]. Uniform void spaces of porous hosts work to synthesize nanostructured metal/aUoy particles as a guest, which are... 

The zeolites are aluminosilicate framework minerals of general formula M", [AI4Sil0lr+>JJ -zH20.y They are characterized by open structures that permit exchange of catioas and water molecules (Fig. 16.2). In the synthetic zeolites the aperture and channel sizes may sometimes be controlled by a sort of template synthesis—the zeolite is synthesized around a particular organoammonium canon. This yields channels of the desired size. The zeolite framework thus behaves in some ways like a clathrate cage about a guest molecule (Chapter 8). The synthesis of zeolites also involves several other factors such as the Al/Si ratio, the pH. the temperature and pressure, and the presence or absence of seed crystals - ... 

Figure 7.1 Schematic representation of target-guided synthesis to generate a ligand (guest) templated by a target biomolecule (host) using the lock and key descriptors of Emil Fischer.

Fig. 12 (A) Template-directed synthesis of capsule 15 with either (B) single or multiple guests (templates).95 (For color version of this figure,...

Directed Template Synthesis - Simple Host-Guest Adducts... 

An example of r-stacking as the driving force in a template synthesis is that by Hiinig et al. [15] of the cationic host molecule (cf. 11), which displays r-acceptor properties. In this case an increase in yield from 3-5% to 16% was observed when an excess of phenanthrene (as 7r-donor guest, see 11) was added to the reaction mixture. This example may even be considered as the first template effect... 

Scheme 3. Template synthesis by Vogtie and co-workers of amide-based catenanes with a concave template The catenation of the macromonocycle 15 with 13a and 14 leads to formation of catenane 17. The guest diacid dichloride 13a and the host 15 are locked in an orthogonal arrangement 16. The functional groups are fixed and thus preorganized for reaction with the diamine 14.

Host-guest chemistry has also given some direction to the template synthesis of zeolite materials. Notable examples are the synthesis of extra-large zeolites SSZ-53 (SFH) and SSZ-59 (SFN) by means of bulky rigid quaternary ammonium SDAs.11111 Burton et al. 

Crego Calama. M. Timmerman. P. Reinhoudt, D.N. Guest-templated selection and amplification of a receptor by noncovalent combinatorial synthesis. Angew. Chem.. Int. Ed. 2000. 39. 755-758. 

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