Organosilicon compounds silicate substitution

Substitution by Alkyls of Zinc, Mercury, and Aluminum. The reaction of alkyls of zinc with ethyl silicate or silicon tetrachloride was the first to be used for the preparation of organosilicon compounds. During the period 1863 to 1880 Friedel and Crafts and later Ladenburg employed zinc dimethyl and zinc diethyl to prepare the corresponding alkyls of silicon and many of the intermediate substitution products as well. The reactions were conducted in sealed tubes heated to about 160° and were of a straightforward metathetical type ... 

Synthesis of Other Silicon Compounds. The substitution route to organosilicon compounds obviously also opens up new avenues to alkyl silicates. For example, as indicated previously, the substitution route is a good avenue to the isomeric alkyl silicates [5.5.1] ( 2H50)ioSie07 and [5.3.3] ( 2H50)ioSie07. The availability of this substitution route for alkyl silicates is of considerable importance, because some of the routes that have been used to make complex alkyl silicates are not good in terms of yield or convenience (22). 

A substitution route to organosilicon compounds is described. In this route, the silicon-oxygen framework of the compound wanted or a framework similar to it, is made by rearrangement of the framework in a silicate or silica or is secured by obtaining a silicate in which the framework is present from an outside source. The compound wanted is made from this framework by displacement of the pendent oxygen atoms and, where needed, by additional rearrangement of it. This route opens a way to syntheses of [(CH3)2SiO] that do not entail the reduction of tetravalent silicon to elemental silicon. 

Goodwin, G. B. Kenney, M. E., A Silicate Substitution Route to Organosilicon Compounds. In Silicon-Based Polymer Science. A Comprehensive Resource, Zeigler, J. M. Fearon, F. W. G., Eds. American Chemical Society Washington, DC, 1990 Vol. 224, pp 251-263. 

---