An improved method for acylation with acid chlorides utilizes the Rathke MgCl2-triethylamine reagent in acetonitrile or ethyl acetate to give ?-keto esters in very high yields: Synthesis, 290 (1993). Alternatively, ?-keto esters can be obtained in high yield by reaction with TMS chloride to generate ethyl trimethylsilyl malonate, followed by in situ reaction with acyl imidazoles or acyl chlorides in the presence of DBU: Tetrahedron Lett., 35, 9323 (1994).