Methanol → (S)-N-[[3-(3-Fluorophenyl)-2-oxo-5-oxazolidinyl]methyl]acetamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a mixture of 3-fluorophenylcarbamic acid 2-methylpropyl ester (300.0 g, 1.42 mol), (S)—N-[2-(acetyloxy)-3-chloropropyl]acetamide (556.1 g, 2.87 mol, 2.02 eq), methanol (90.03 g, 2.81 mol, 1.98 eq) and N,N-dimethylformamide (500 ml) is added a slurry of lithium t-amylate (401.3 g, 4.27 mol, 3.00 eq) in heptane (1 liter) while maintaining −4 to 7° C., followed by heptane (100 ml). The mixture is then stirred at 19 to 20° C. for 21 h. The reaction mixture is then added to a mixture of ammonium chloride (228 g, 4.26 mol, 3.00 eq), water (2.0 liter) and toluene (1.0 liter) while maintaining 8 to 10° C. The reaction mixture is rinsed in with a mixture of water (100 ml), saturated ammonium chloride (50 ml) and toluene (100 ml). The precipitate is collected by vacuum filtration and washed with heptane (1 liter) and water (1 liter) and dried in a nitrogen stream to give 252.4 g of crude product. This is triturated in acetonitrile (1 kg) at 90° C. and the slurry concentrated under reduced pressure to 800 ml total volume. Toluene (1900 ml) is added while concentrating to maintain 800 ml total volume. Water (1 liter) and heptane (1 liter) are added and the precipitate collected by vacuum filtration, washed with water (750 ml) and heptane (250 ml) and dried in a nitrogen stream to give the title compound (225.7 g, 63.0%).

Herkunft & Nachweise