Triethoxysilyl groups

As an organic polymer, poly(tetramethylene oxide) was also used for the preparation of ceramers. The mechanical properties in these cases were much improved in comparison with those for hybrids from polysiloxanes. In these poly (tetramethylene oxide)-silica hybrids, the effect of the number of functional triethoxysilyl groups was examined [13]. As shown in Fig. 2, more multifunctional organic polymer produced more crosslinked hybrid networks. This means that the more rigid the structure in the hybrids is, the higher the modulus and the lower swelling property. 

Corma et al. [55] have prepared chiral Cu(I) complexes with substituted pyrrolidine ligands bearing a triethoxysilyl group (Scheme 24). 

As neutral carriers for the chemical modification, 16-crown-5 and calix[4]arene derivatives possessing a triethoxysilyl group (7) and (8) were designed for Na sensors. Triethoxysilylethyl-16-crown-5(7) was then mixed with a silicone-rubber precursor for the membrane fabrication accompanying covalent bonding of the neutral carrier. Comparison of IR spectra before and after extraction of the nonbonded neutral carrier... 

It is also worthwhile to outline at this place the immobilization procedure that was used for the preparation of type I CSPs A bifunctional linker with a terminal isocyanate on one side and a triethoxysilyl group on the other end (3-isocyanatopropyl triethoxysilane) was reacted with the native cinchona alkaloids quinine and quinidine and subsequently the resultant carbamate derivative in a second step with silica [30], Remaining silanols have been capped with silane reagents, yet, are less detrimental for acidic solutes because of the repulsive nature of such electrostatic interactions. CSPs prepared in such a way lack the hydrophobic basic layer of the thiol-silica-based CSPs mentioned earlier, which may be advantageous for the separation of certain analytes. 

A rhodium complex 4b or 5b, bearing a triethoxysilyl group (0.2 mmols) in dry dichloromethane was added to a suspension of zeolite (1 g, previously dried at 140°C/0.01 mm Hg) in dry toluene and the mixture was stirred for 24 hours at room temperature. The solid was then filtered and Soxhlet-extracted with dichloromethane-diethyl ether (1 2) for 12 hours to remove the remaining non-bonded complex, and dried in vacuo. The analytical data for the supported complexes are shown in Table 3. 

Delmarre et al. grafted cobalt (11) porphyrins by using a triethoxysilyl group and pure tetramethoxysilane as the precursor in a porous sol-gel matrix for the detection of amines [55]. The results on pyridine sensing show that the diffusion of pyridine occurs with a lower rate than that in organic matrices. 

Very interesting arylene-bridged polysilsesquioxane networks were described by Loy and Shea [279] and Shea et al. [280]. Aromatic hydrocarbons containing two (or more) triethoxysilyl groups were used as the starting compounds ... 

The triethoxysilyl group constitutes the reactive part of the silane, forming a covalent bond with the carbon black. 

Ikai T, Yamamoto C, Kamigaito M, Okamoto Y (2007) Immobilization of polysaccharide derivatives onto silica gel Facile synthesis of chiral packing materials by means of intermo-lecular polycondensation of triethoxysilyl groups. J Chromatogr A 1157 151-158... 

Preparation of dyes with a terminal triethoxysilyl group to connect with a network of the matrix gel should be performed under neutral conditions, because the triethoxysilyl group hydrolyzes and condenses in the presence ofwater and an acid or a base. For example, the reaction ofphenoxazine dye with triethoxysilylpropylamine in refluxing ethanol yielded... 

Scheme 28-1. Preparations of reactive dyes having a terminal triethoxysilyl group.

Two kinds of synthetic approaches are illustrated in Scheme 11 and 12, respectively. In approach (I), maltopentaonolactone (29) was firstly prepared, followed by reaction with 3-aminopropyltriethoxysilane to obtain the maltooligosaccharide (30) bearing triethoxysilyl group. Amylose chains were then extended by the phosphorylase-catalyzed enzymatic... 

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