2000ml four mouth -bottle into tetrahydrofuran 500g, 1,3,5-trifluorobenzene 132g, cooled to -60 ° C, in -60 ~ -90°C,, dropwise; 2. 5N 500ml Butyl lithium, drop about I.5h, add heat insulation 2h, system drops add 80g N, N-dimethylformamide, and 100 g of a tetrahydrofuran solution, control temperature below -60 °C, Then add heat insulation 3h, and heating insulation, heating up to -30 °C, and set aside. Another 3000ml four-mouth bottle into 650g water, 226g 30 % hydrochloric acid, 190g sodium chloride, stirring, then add dropwise at 20 ° C above-mentioned -temperature reaction solution adding completed, insulation 0 5h, layered, Water layer with 200g methyl tert butyl ether extraction Combined organic layer, steaming solvent 2,4,6-Trifluorobenzaldehyde 145 g.
