Templates supramolecular

Albrecht M (2004) Supramolecular Templating in the Formation of Helicates. 248 105-139 Ando T, Inomata S-I, Yamamoto M (2004) Lepidopteran Sex Pheromones. 239 51-96 Angyal SJ (2001) The Lobry de Bruyn-Alberda van Ekenstein Transformation and Related Reactions. 215 1-14... 

M. S. Wong, H. C. Huang, and J. Y. Ying, Supramolecular-templated synthesis of nanoporous zirconia-silica catalysts, Chem. Mater. 14(5), 1961—1973 (2002). 

Eurlan RLE, Otto S, Sanders JKM. Supramolecular templating in thermodynamically controlled synthesis. Ptoc Natl Acad Sci USA 2002 99 4801-4804. 

A second experiment should prove that macromonocycles are actually the intermediate supramolecular templates in the course of catenane formation. Therefore macromonocycle 17 was reacted with 5 and 3, and the first [2]catenane 18 of the amide type consisting of two different macromonocycles was isolated (Figure 8). Unsymmetric catenanes like 18 can be identified unambiguously by mass spectrometry, because the corresponding tetrameric macromonocycle can not be formed in this reaction sequence. This confirms the presumption that catenation here proceeds via a macrocycle rather than via intertwining open chain units. 

Since the discovery of the M41S materials with regular mesopore structure by Mobils scientists [1], many researchers have reported on the synthetic method, characterization, and formation mechanism. Especially, the new concept of supramolecular templating of molecular aggregates of surfactants, proposed as a key step in the formation mechanism of these materials, has expanded the possibility of the formation of various mesoporous structures and gives us new synthetic tools to engineer porous materials [2],... 

This study demonstrated that the micro-mesoporous composite materials could be synthesized with two-step treatment by microwave using two different templates system with TPABr and MTAB. This formation was controlled by the self-assembly formation of supramolecular templates between MTA micelles and SiO /TPA gels. As varying microwave irradiation time of micro-mesoporous materials, gradually transition from the mesophase to micro-mesophase was occurred. These materials have higher dm spacing of mesoporous materials and lead to transition from mesophase to micro-microphase by an increment of synthetic time, while the calcined products is formed with bimodal and trimodal pore size distribution under microwave irradiation within 3 h. From TG-DTA and PL analysis, the self-assembly formation of supramolecular templates between MTA+ micelles and SiO /TPA+ gels were monitored. 

Since the first synthesis of mesoporous M41S alumosilicates in 1992 [1,2] numerous systems of mesoporous materials have been reported. The principle method of these syntheses consists of the utilisation of lyotropic liquid crystals as supramolecular templates, which act as structure directing agents in order to mesostructure inorganic building units. 

There are nevertheless a number of recent indicators that the biotechnological challenge has fostered the chemists creativity. Some of them are able to self-assemble components, thanks to a clever use of surfactants as supramolecular templates. Inorganic complex structures presenting a variety of interesting shapes such as discs or helix can be obtained at a mesoscale or in some cases at the macroscopic level. [28]... 

An additional disadvantage of the use of covalently bound templates, that is not found in statistical reactions or by the use of supramolecular templates, is the requirement to attach the bisacetylenic building blocks of the macrocycle to the template. So far this has been an additional step in a linear reaction sequence, thus reducing the overall product yield. Whereas this extra step in the case of the cyclotrimerization is overcompensated by a considerable yield increase of the desired shape-persistent ring, this argument does not hold for the cyclodimerization where statistical reactions already give yields of the order of 50-60 %. 

The most recent phenomenon observed to occur within the confines of 24 is the stereoselective photodimerisation of olefins [68]. Without the presence of the cage, the dimerisation of 28 results in a mixture of the syn- and anti- isomers (29 and 30 respectively, Scheme 8). With the cage present, two molecules of 28 are encapsulated before the photodimerisation occurs. Within the cavity the syn isomer is the only one capable of forming for steric reasons. This type of selectivity has been observed for several related compounds. Recently, photodimerisation has also been observed to be controlled by supramolecular templation in the solid state [69]. 

Ying, J. Y, Mehnert, C. P, and Wong, M. S., Synthesis and applications of supramolecular-templated mesoporous materials. Angew. Chem. Int Ed. 38,56 (1999). 

The synthesis of molecular sieves with large pores is of great importance for many applications such as catalysis, separation, adsorption and fabrication of various quantum materials [1-7]. With the recent discovery of hexagonal and cubic large pore mesoporous materials (SBA-15, SBA-16, FDU-1) [2,3], block copolymers have turned out to be valuable supramolecular templates for the synthesis of ordered large pore mesoporous materials because of their facile structure-directing ability, low-cost commercial availability and biodegradability. 

J.Y. Ying, C.P. Mehnert, M.S. Wong, Synthesis and Applications of Supramolecular-Templated Mesoporous Materials , Angew. Chem. Int. Ed., 38,56 (1999)... 

Ying JY, Mehnert CP, Wong MS (1999) Synthesis and appheations of supramolecular-templated mesoporous materials. Angew Chem Int Ed 38 56... 

New catenane (cf. 17) and rotaxane (cf. 20) types have been obtained via supramolecular template syntheses The amide-based interlocked structures can be designed by appropriate choice of building units (cf. 13, 14) to form stable out/out, in/in and in/out isomers (cf. 17a, 17b), which can be separated [19]. It can be demonstrated that one of the two macromonocycles (cf. 15) of the... 

On the basis of the hypothesis of the intertwining mechanism described above, the syntheses of the first amide-based rotaxanes (Structures 20a, 20b) were successful as well [21], Their (supramolecular template) syntheses were strikingly simple. The central part of the axle 13a is added to a tetralactam wheel and subsequently capped with triphenylmethane stoppers. The macromonocycle ( wheel ) provides the receptor cavity for the axle and the stoppers confirm the mechanical bond between wheel and axle . 

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