Silicon-Based Dendrimers

Siloxane and Carbosiloxane Based Dendrimers: Synthesis, Reaction Chemistry, and Potential Applications

“…Several approaches towards this exist. [7,14] One example relies upon the introduction of cholesterol building blocks as end-grafted units. Examples of this new class of liquid crystalline (LC) materials, e.g., MeSi(OSiMe(OSiMe 2 (OSiMe 2 (CH 2 ) 10 COO±Chol)) 2 ) 3 (32) (Chol = cholesteryl), in which a first generation polyorganosiloxane dendrimer is linked to cholesteryl mesogenic groups via CH 2 spacers, can be synthesized through treatment of the terminal chlorinated den- 10 COO±Chol in presence of pyridine ( Fig.…”

“…[1±3,7±13] Of the multitude of dendrimers reported, we focus in this article on siloxane and carbosiloxane dendrimers, as well as dendrimers that contain siloxane and carbosiloxane sub-units (Si±O±Si, Si±O±C, C±Si±O±Si±C, ...), due to the increasing attention paid to them in dendrimer chemistry recently, since the formation of Si±O bonds can be easily generated. [14] In this respect various synthetic methods for the preparation of siloxane-and carbosiloxane-based dendritic molecules possessing reactive and potentially useful organic, inorganic, or even organometallic building blocks as terminal units, which themselves can participate in numerous chemical reaction processes, will be described. Also, their properties, physical behavior, their characteristic reaction chemistry, and their development for potential applications will be discussed.…”

Adamantanes, Nortricyclenes, and Dendrimers with Extended Silicon Backbones

“…The situation concerning dendrimers containing silicon± silicon bonds [15,16] is similar to that for the above-mentioned nortricyclanes and adamantanes. Dendrimers containing isolated silicon atoms in the backbone are quite well known, but again very few studies deal with compounds containing silicon±silicon bonds.…”

“…[9] One therefore would expect a highly stable molecule such as adamantane to have a counterpart in silicon chemistry. Impure Si 10 Me 16 was in fact obtained from the reaction of a mixture of MeSiCl 3 and Me 2 SiCl 2 with potassium in very low yield and was identified by its 1 H NMR spectrum. [10] Neither Si 10 H 16 nor nortricyclenes Si 7 R 10 have been described so far.…”

“…[1] Many derivatives with various substitution patterns, including the parent hydrocarbons C 7 H 10 and C 10 H 16 and compounds with backbones composed of carbon and first-row heteroatoms such as oxygen or nitrogen, have been described in the literature. [2] Adamantanes and nortricyclenes are also common ring systems in the inorganic and organometallic chemistry of the heavier elements of Groups 15 and 16, such as phosphorus, arsenic, sulfur and selenium.…”