Silanetriols tubes

The N-bonded silanetriol (2,4,6-Me3C6H2)N(SiMe3)Si(OH)3 [26] organizes itself in a tubular form which is made up of four linear columns. Further, these columns are displaced with respect to each other by a 90° rotational relationship. As a result of this arrangement there is an interesting formation of silanetriol tubes in the crystal which contain a hydrophilic interior and a hydrophobic exterior. 

The silanetriol (1) is air-stable as a solid and can be manipulated without special care. It is very soluble in most organic solvents. The crystal structure of the A-bonded silanetriol [2,4,6-Me3C6H2N(SiMe3)]Si(OH)3 has been determined by X-ray diffraction and shows an interesting formation of silanetriol tubes in the crystal that contain a hydrophUic interior and a hydrophobic exterior. ... 

Using this methodology, the size and shape of the cavity determines which oligomer will be isolated (Scheme 10.7). Indeed, bowl 16 produces dimer 19 whereas the small coordination tube 21, which allows the complexation of only one molecule of the reactant, affords monomer 18, a silanetriol. In this case, starting from 4 equiv of 3,5-bis(3-pyridyl) pyridine 20 and 6 equiv of Pd(en)(N03)2, tube 21 can only be prepared in situ by means... 

The different steric situation at these silanetriols is clearly seen in the X-ray structures. Based on hydrogen-bonded networks silanetriols are arranged in the solid state in a variety of supramolecular structures [1]. Whereas 1 crystallizes as a hemihydrate in a double-sheet structure [2] (Fig. 3), 2 forms a tube structure [3] (Fig. 4). 

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