反应详情

温度

0 °C

To a solution of 1.75 g of tert-butyl 1-hydroxy-3-methylbutan-2-ylcarbamate (Formula 20) in 25 mL of DMSO was added 3.6 mL of triethylamine. The solution was cooled to 0° C. and 4.1 grams of sulfur trioxide pyridine complex in 25 mL of DMSO was added. The reaction mixture was stirred at room temperature for 1 hour. Then, the mixture was poured onto ice-water and extracted with ethyl acetate. The organic layers were washed with 10% acetic acid, water, 5% sodium bicarbonate, and brine, dried over sodium sulfate and concentrated. Column chromatography (30% ethyl acetate/hexane) gave 1.25 g of tert-butyl 3-methyl-1-oxobutan-2-ylcarbamate (Formula 21) as a clear oil. 1H NMR (300 MHz, CDCl3) δ 0.95 (d, J=7.32 Hz, 3H), 1.03 (d, J=6.83 Hz, 3H), 1.45 (s, 9H), 2.27-2.29 (m, 1H), 4.24-4.26 (m, 1H), 9.65 (s, 1H).

1. additionThen, the mixture was poured onto ice-water
2. extractionextracted with ethyl acetate
3. washThe organic layers were washed with 10% acetic acid, water, 5% sodium bicarbonate, and brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated