Description
Triethoxysilane is an organosilicon compound with the formula HSi(OC2H5)3. It is a colourless liquid used in precious metal-catalysed hydrosilylation reactions. The resulting triethoxysilyl groups are often valued for attachment to silica surfaces.Compared to most compounds with Si-H bonds, triethoxysilane exhibits relatively low reactivity. Like most silyl ethers, triethoxysilane is susceptible to hydrolysis. As reducing agent, triethoxysilane can for example be used in reduction of amides, reduction of carbonyl compounds in the presence of cobalt(II) chloride as catalyst, Cu-catalyzed reductive hydroxymethylation of styrenes, and Rh-catalyzed hydrodediazoniation.
Chemical Properties
Colorless, clear liquid
Physical properties
bp 134–135 °C; d 0.89 g cm?3.
Uses
Triethoxysilane is useful reagent for the hydrosilylation of carbon–carbon multiple
bonds; reducing agent for carbonyl groups
Uses
Triethoxysilane is used in metal catalyzed hydrosilylation reactions.
Application
Reduces esters in the presence of zinc hydride catalyst.
Reduces aldehydes and ketones to alcohols via the silyl
ethers in presence of fluoride ion. Gives 1,2-reduction of
enones to allyl alcohols.
General Description
Liquid. Used as a reducing agent.
Air & Water Reactions
May become pyrophoric, by generation of silane
Reactivity Profile
Triethoxysilane has been involved in cases where Triethoxysilane has disproportionated, generating silane (SiH4) which has a history of being pyrophoric.
Health Hazard
Toxicity is similar to silanes. Silanes are moderately irritating to skin, eyes, and mucous membranes. Silane compounds are toxic.
Fire Hazard
When heated to decomposition, Triethoxysilane emits acrid smoke and fumes.
Flammability and Explosibility
Highly flammable
Safety Profile
Poison by intravenous route.Moderately toxic by inhalation. Flammable liquid. Whenheated to decomposition it emits acrid smoke andirritating fumes.
Purification Methods
Fractionate it using a column packed with glass helices of ca 15 theoretical plates in an inert atmosphere. Store it in aliquots in sealed ampoules because it is sensitive to moisture. [Spauschus et al. J Am Chem Soc 72 1377 1950, MacKenzie et al. J Am Chem Soc 72 2032 1950, Havill et al. J Org Chem 13 280 1948, Beilstein 1 IV 1359.]
