1.3.5- Benzene-tris-tetrazole

The same Lewis acid-catalyzed reaction of the cyanosilylation of aromatic aldehydes was investigated by Long et al. [85]. The catalytic activity of the sodalite-type compound Mn3[Mn Cl3(btt)g(CH30H),Q] (BTT is l,3,5-benzene-tris(tetrazol-5-yl)) was studied. This material is a 3D porous structure with a pore diameter of 1 nm. It was assumed that each of the two types of Mn(II) sites exhibits catalytic activity. The distinctive features of this catalyst are the high conversions in the case of small substrates and a good substrate size selectivity, properties that are consistent with the occurrence of the catalytic process in the channels. The surface of the framework bears open Mtf+ ions, which act as Lewis acid sites. 

Although SiCh 57 has been employed, e.g., in the presence of sodium azide to convert ketones into tetrazoles (Section 5.3), to condense cyclopentanone in high yields into 1.2.3.4.5.6-tris(trimethylene)benzene (Section 9.2), or used for the condensation of amino acids to polyamides (Chapter 14) with formation of Si02, enol-trimethylsilyl ethers 107 a of ketones such as cyclohexanone are cleanly converted by SiCh 57 in the presence of Hg(OAc)2 into the trichlorosilylenol ether 116, which adds benzaldehyde in the presence of the asymmetric catalyst 117 to give... 

A second example of homochiral columns formed by discotics are the complexes of tetrazoles (59 and 60) with l,3,5-tris(4,5-dihydroimidazol-2-yl)benzene (61).74 Four molecules self-assemble to give a supramolecular disc and these discs subsequently form columns in nonpolar solvents. Chiral discs were obtained from the self-assembly of the chiral tetrazole (60) with 61. The chirality of the side chains was found to induce a bias in the helic-ity of the supramolecular assembly. Sergeants-and-soldiers measurements75 were performed for which chiral (60) and achiral (59) molecules were mixed. The experiments showed no amplification of chirality, thus revealing that in these systems chirality transfer from the side chains into the column is... 

Complexation of Tetrazoles with 1,3,5-Tris 4089 (4,5-dihydroimidazol-2-yl)benzene... 

Another example of supramolecular columnar polymers formed by the combined use of hydrogen bonding and arene—arene interactions are the complexes of tetrazoles and l,3,5-tris(4,5-dihydroimidazol-2-yl)-benzene (53, Figure 28).231 Four molecules self-assemble to give a supramolecular disc-shaped molecule, which subsequently polymerizes into columns when in nonpolar solvents. Upon formation of a... 

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