Diphenylsilane

Chemical properties

clear colorless liquid

The Uses of Diphenylsilane

Thiocarbonyl derivatives of secondary alcohols are readily reduced by diphenylsilane in a radical chain process at room temperature using triethylborane-air as an initiator. An improved radical chain procedure for the deoxygenation of secondary and primary alcohols using diphenylsilane as hydrogen atom donor and triethylborane-air as initiator. Diphenylsilane is a reagent in the invention of radical reactions for deoxygenation of alcohols via their thiocarbonyl derivatives, deamination via isonitriles, and dehalogenation of bromo- and iodo- compounds by radical chain chemistry. Fluorescent film sensor for vapor-phase nitroaromatic explosives via monolayer assembly of oligo(diphenylsilane) on glass plate surfaces. Reductions of carboxylic acid derivatives by silanes in the presence of rhodium complexes were studied. Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by [RhCl (cod)] 2/4PPh 3 or [RhCl (PPh 3) 3] at room temperature in up to 99% yields. Sequential C- Si bond formations from diphenylsilane and its application to silanediol peptide isostere precursors.

What are the applications of Application

Used in the preparation of silyl-substituted alkylidene complexes of tantalum. Used in the ionic reduction of enones to saturated ketones. Used in the reductive cyclization of unsaturated ketones. Reduces esters in the presence of zinc hydride catalyst. Reduces α-halo ketones in presence of Mo(0). Reduces thio esters to ethers. Reduces esters to alcohols with Rh catalysis. Employed in the asymmetric reduction of methyl ketones and other ketones. Reductively cleaves allyl acetates.

Purification Methods

Dissolve it in Et2O, mix slowly with ice-cold 10% AcOH. The Et2O layer is then shaken with H2O until the washings are neutral to litmus. Dry over Na2SO4, evaporate the Et2O and distil the residual oil under reduced pressure using a Claisen flask with the take-off head modified into a short column. Ph2SiH2 boils at 257o/760mm, but it cannot be distilled at this temperature because exposure to air leads to flashing, decomposition and formation of silica. It is a colourless, odourless oil, miscible with organic solvents but not H2O. A possible impurity is Ph3SiH which has m 43-45o and would be found in the residue. [West & Rochow J Org Chem 18 303 1953, Benkhesser et al. J Am Chem Soc 74 648 1952, Gilman & Zuech J Am Chem Soc 81 5925 1959, Beilstein 16 IV 1366.]