In the presence of an anionic initiator (M X), the reagent reacts with aldehydes and ketones to give a trimethylsilyl ether, the net product of insertion of the carbonyl into the Si-CF bond. Hydrolysis  gives trifluoromethyl methanols. The reagent also converts esters to trifluoromethyl ketones. A typical initiator is a soluble fluoride-containing species such as tetrabutylammonium fluoride; however, simple alkoxides such as KOtBu are also effective. The mechanism begins by generation of Si(CH)X and a highly reactive [CF] (trifluoromethide) intermediate. The [CF] attacks the carbonyl to generate an alkoxide anion. The alkoxide is silylated by the reagent to give the overall addition product, plus [CF], thus propagating an anionic chain reaction. The reagent competes with the carbonyl for the reactive intermediate, rapidly sequestering [CF] in a reversibly-generated -ate complex [(CF)Si(CH)]. This -ate complex is unable to react directly with the carbonyl, resulting in powerful inhibition of the chain reaction by the reagent. This inhibitory process is common to all anion-initiated reactions of the reagent, with the identity of the counter-cation (M) playing a major role in controlling the overall rate.
The reagent has largely supplanted trifluoromethyllithium, which is not isolable and rapidly decomposes to yield lithium fluoride and difluorocarbene.