Triphenylsilane

Chemical properties

Triphenylsilane is an off-white solid that is soluble in most organic solvents. It is used in certain cases for the preparation of triphenylsilyl ethers, which serve as alcohol-protecting groups. The triphenylsilyl group is considerably more stable (about 400 times) than the TMS group toward acidic hydrolysis.

The Uses of Triphenylsilane

Triphenylsilane is reducing agent for esters, xanthates, and polychloroalkanes; protecting group for alcohols. It takes part in the reactions of Deoxygenations, Hydrosilylations, Lewis Acid-assisted Hydrosilylations, Heteroatom Reductions, Multiple Bond Reductions, Alkene Hydrogenations, Silylations, etc.

The Uses of Triphenylsilane

Triphenylsilane acts as a reactant or reagent for catalytic hydrogen deuterium exchange reactions of silanes, to be oxidized by carbon nanotube-gold nanohybrids, for hydrolysis by ruthenium complexes, for hydrosilylation to produce enolsilanes, for synthesis of bromosilanes, for ozone oxidation of silyl-alkenes for synthesis of α-O-silylated acyloin derivatives. It is used to synthesize hydrido silyl and bis(silyl) bis(imidazolinylidene) nickel complexes.

What are the applications of Application

More effective radical-based reagent for reduction of organic halides than the trialkylsilanes.
Compares well with tri-n-butyltin hydride in reduction of enones to ketones.
Shows good selectivity in the reduction of cyclic hemiacetals.
Converts O-acetyl furanoses and pyranoses to deoxy sugars.
Hexaphenyldisiloxane can be conveniently made by the action of aqueous alkali on triphenylsilane, Ph3SiH.
Tristriphenylsilylbismuth, (Ph3Si)3Bi, is made similarly from triethylbismuth and triphenylsilane: Et3Bi+3Ph3SiH==Heat==(Ph3Si)3Bi+3EtH.

Preparation

Triphenylsilane can be synthesized by reducing phenylsilane (PhSiH3) with a reducing agent such as lithium aluminum hydride (LiAlH4). The overall reaction equation is as follows:
3 PhSiH3 + 2 LiAlH4 → C18H16Si + 2 LiH + 2 AlH3
This reaction is typically carried out in anhydrous conditions and under inert gas atmosphere.

Purification Methods

Purify it by recrystallisation from MeOH. [Gilman & Zuech J Am Chem Soc 81 5925 1959, Westermark Acta Chem Scand 9 947 1955, IR: Kaplan J Am Chem Soc 76 5880 1954, Beilstein 16 II 605, 16 III 1199, 16 IV 1369.]