Trifluoromethyltrimethylsilane (known as Ruppert-Prakash reagent, TMSCF) is an organosilicon compound with the formula CFSi(CH). 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 by Ingo Ruppert and further developed as a reagent by G. K. Surya Prakash.