[N+:1]([O-:4])(O)=[O:2].[F:5][C:6]([F:19])([F:18])[O:7][C:8]1[CH:17]=[CH:16][CH:15]=[CH:14][C:9]=1[C:10]([O:12][CH3:13])=[O:11]>>[CH3:13][O:12][C:10](=[O:11])[C:9]1[CH:14]=[C:15]([N+:1]([O-:4])=[O:2])[CH:16]=[CH:17][C:8]=1[O:7][C:6]([F:5])([F:19])[F:18]Fuming nitric acid (5 mL) was cooled on an ice bath. Methyl 2-(trifluoromethoxy)benzoate (5 g, 22.7 mmol) was slowly added within 30 min keeping the temperature below 15° C. The reaction was then stirred at 60° C. for 1 hour and 2 hours at room temperature. The mixture was poured on ice water whereupon an oil separated. The aqueous supernatant was decanted and additional water (50 mL) was added to the oil. After neutralisation with sodium hydrogen carbonate, the mixture was extracted with ethyl acetate (25 mL). The aqueous phase was extracted with ethyl acetate (15 mL) once more. The combined organic phases were washed with saturated sodium chloride (2×15 mL), dried (magnesium sulphate), and concentrated in vacuo to give 5.69 g of 5-nitro-2-trifluoromethoxybenzoic acid methyl ester.
Wird geladen…