Introduction
Tetraacetoxysilane is a clear to yellowish liquid with acrid odor of acetic acid (vinegar). It hydrolyzes in the presence of moisture (acetic acid is released) to form silanols, which can react with themselves to pro-duce siloxanes or bind to inorganic substrates.
Chemical Properties
Off-white crystalline solid
Uses
Silicon tetraacetate is used in the preparation of silicon dioxide thin films by a direct photochemical vapor deposition method. It serves as a precursor to prepare silicon complexes with monofunctional bidentate Schiff bases. It is also used as an alternative to silicon hydride and alkoxide for low-temperature silicon dioxide production. Further, it reacts with ethanol in the absence of water to get silica gel and ethyl acetate. In addition, it is employed as a sol-gel precursor.
General Description
Silicon tetraacetate is an alternative to silicon hydride and alkoxide for low-temperature SiO
2 production. Silicon tetraacetate reacts with ethanol in absence of water to form silica gel and ethyl acetate. Silicon tetraacetate is reported as a sol-gel precursor.
Purification Methods
It can be crystallised from mixtures of CCl4 and pet ether or Et2O, or from acetic anhydride and then dried in a vacuum desiccator over KOH. Ac2O adheres to the crystals and is removed first by drying at room temperature, then at 100o for several hours. It is soluble in Me2CO, is very hygroscopic and effervesces with H2O. It decomposes at 160-170o. [Schenk in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 701 1963, Beilstein 2 H 171.]
