Density 963 kg/m³ Pubchem 552549 Molar mass 142.20 g·mol−1 | Appearance colorless liquid Chemical formula C4H9F3Si | |
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Boiling point 54 to 55 °C (129 to 131 °F; 327 to 328 K) | ||
Trifluoromethyltrimethylsilane (Ruppert's reagent) is an organosilicon compound with the formula CF3Si(CH3)3. It is a colorless liquid. The compound is a reagent used in organic chemistry for the introduction of the trifluoromethyl group. The compound was first prepared in 1984 in Ingo Ruppert and further popularized Surya Prakash.
Contents
Preparation
The reagent is prepared from trimethylsilyl chloride and bromotrifluoromethane in the presence of a phosphorus(III) reagent that serves as a halogen acceptor.
Use in organic synthesis
In the presence of a source of fluoride, the reagent forms the -ate complex [[CF3Si(CH3)3F]]−. This species attacks aldehydes and ketones. The net reaction is insertion of the carbonyl into the Si-CF3 bond to give a trimethylsilyl ether. Hydrolysis the gives trifluoromethyl methanols. A typical fluoride-containing catalyst is tetrabutylammonium fluoride. It converts esters to trifluoromethyl ketones.
The reagent has largely supplanted trifluoromethyllithium, which is not isolable and rapidly decomposes to yield lithium fluoride and difluorocarbene.