Ethyl 4-fluoro-3-(trifluoromethyl)benzoate synthesis

Yield:67515-63-3 74%

Reaction Conditions:

with sulfuric acid in ethanol; for 18 h;Heating / reflux;

Steps:

113

Preparation 113; 4-Fluoro-3-trifluoromethvl-benzoic acid ethvl ester; Concentrated sulfuric acid (0.3mL) was added to a solution of 4-fluoro-3- (trifluoromethyl) benzoic acid (10g, 48mmol) in ethanol (70mL) and the resulting mixture was heated under reflux for 18 hours. The solvent was then evaporated under reduced pressure and the residue was dissolved in ethyl acetate (150mL) and washed with sodium hydrogen carbonate solution and brine. The organic solution was dried over magnesium sulfate and concentrated in vacuo to give a brown liquid. The liquid was purified by column chromatography on silica gel, eluting with ethyl acetate: pentane, 10: 90, to afford the title compound as a colourless oil in 74% yield 7. 9g.'H NMR (400MHz, CDCI3) d : 1.40 (t, 3H), 4.40 (q, 2H), 7. 25 (m, 1H), 8. 25 (m, 1H), 8.32 (d, 1H)

References:

WO2005/82866,2005,A2 Location in patent:Page/Page column 102