Ammonium Chloride → 4-(1-Methylpiperidin-4-yloxy)-3-trifluoromethylbenzonitrile

Beteiligte Stoffe

Reaktionsschritte

6.68 g of potassium t-butoxide was suspended in 40 ml of anhydrous tetrahydrofuran and a solution of 6.85 g of 1-methyl-4-hydroxypiperidine in 20 ml of anhydrous tetrahydrofuran was added dropwise over 35 minutes while stirring under ice-water cooling and further the mixture was stirred for 30 minutes. On the other hand, 7.50 g of 4-fluoro-3-trifluoromethylbenzonitrile was dissolved in 40 ml of anhydrous tetrahydrofuran, the mixture was stirred under cooling in a dry ice/acetone bath, and the solution prepared earlier was added dropwise at the internal temperature of −70° C. After adding dropwise, the reaction solution was stirred overnight while naturally heating up to room temperature. The reaction solution was ice-cooled, an aqueous saturated ammonium chloride solution and water were added thereto, and then the solvent was distilled off under reduced pressure. The residue was subjected to extraction with ethyl acetate twice. The extracts were washed in turn with water and saturated saline and dried over anhydrous magnesium sulfate, and then the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography to obtain 7.31 g of the objective compound as colorless crystals.

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