Chemical Properties
Water-clear liquid. B.p. 186°C. Hydrolyzes easily, yielding
GeO2.
Uses
It is a sol-gel intermediate for optical fibers and photosensitive.
Preparation
A solution of 9.8 g. of metallic sodium in a considerable excess
of absolute alcohol is prepared. A solution of 20 g. of GeCl4 in absolute ether is added with
stirring and exclusion of moisture. The mixture is refluxed for
several hours and then decanted from the NaCl which separates.
The solid is washed with absolute ether. The washings are combined with the main solution and the solvent is then driven off
in vacuum. Finally, the tetraethoxygermane is distilled. It is
redistilled at atmospheric pressure.
Purification Methods
Distil it through a 10cm Vigreux column (p 11) under reduced pressure. Alternatively distil it through a Fenske glass helices (p 11) column fitted with a total condensation variable take-off stillhead. Fractionate it under reduced pressure using a reflux ratio of 10:1. [Johnson & Fritz J Am Chem Soc 75 718 1953, Bradley J Chem Soc 4916 1956, Beilstein 1 IV 1308.]
