Abstract α-Acylation of the ketene silyl acetal of methyl β, β, β-trifluoropropionate and α- allylation via the ester enolate Claisen rearrangement of the 2-alkenyl trifluoropropionates are described which provide the corresponding α-CF 3 β-ketoesters and α-CF 3 γ, δ- unsaturated acids, respectively.