General procedure: Under standard Schlenk operating conditions, the reaction system is first evacuated and backfilled three times with dry pure nitrogen. To a pre-dried Schlenk tube fitted with a magnetic stirring bar, palladium catalyst (see Tables 1 to 4 for specific types and amounts), ligand (see Tables 1 to 4), N,N-dimethylpyridin-4-amine (DMAP, see Tables 1 to 4), and monoethyl malonate potassium salt (see Tables 1 to 4) are added sequentially. Subsequently, the reaction tube was evacuated and backfilled with argon, and this process was repeated three times. Under argon protection, p-bromobenzotrifluoride (see Tables 1 through 4) and an appropriate amount of solvent (see Tables 1 through 4) were added via syringe. The reaction tube was sealed and stirred for 10 minutes at room temperature. Afterwards, the reaction tube is connected to a Schlenk line pre-filled with argon and placed in an oil bath preheated to 140-150°C and the reaction is stirred for 20-25 hours. After completion of the reaction, the reaction was cooled to room temperature, the reaction mixture was diluted with ether and the yield of ethyl 4-(trifluoromethyl)phenylacetate was determined by gas chromatography using 1,3-dimethoxybenzene as an internal standard.
