Hydrogen Bromide → methyl 2-bromo-3-[4-methoxy-3-[N-(4-trifluoromethylbenzyl)]carbamoylphenyl]-propionate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 17.3 g of 5-amino-2-methoxy-N-(4-trifluoromethylbenzyl)benzamide in 170 ml of acetone and 85 ml of methanol were added 43 ml of 47% solution of hydrobromic acid and 17 ml of aqueous solution of 4.15 g of sodium nitrite under cooling with ice-salt, and the mixture was stirred for 10 minutes. To the reaction mixture were added 26 ml of methyl acrylate, and, after heated to 30° C., 1.04 g of cupric oxide were added little by little, and the mixture was stirred further for 1 hour at 40 to 50° C. Solvent was distilled off under reduced pressure, and 25% aqueous ammonia was added to the residue, which was extracted with ethyl acetate. The organic layer was washed with water and saturated brine in sequence and dried over anhydrous sodium sulfate. Solvent was distilled off under reduced pressure, and the residue obtained was crystallized from hexane-ethyl acetate, then the crystals were collected by filtration to obtain 10.3 g of methyl 2-bromo-3-[4-methoxy-3-[N-(4-trifluoromethylbenzyl)]carbamoylphenyl]-propionate as light brown crystals.

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