反应详情

温度

0 °C

4.31 g 1-Dimethylamino-4-hydroxyamino-piperidine-4-carbonitrile (from Step 2) is dissolved in 70 ml tetrahydrofuran. 3.34 g sodium bicarbonate is added, and the mixture cooled to 0° C. Then at 0° C., a solution of (2,4,6-trimethyl-phenyl)-acetyl chloride in 30 ml tetrahydrofuran is added slowly. The mixture is allowed to warm to room temperature and stirred for 4 hours. The water is added and three times extracted with ethyl acetate. The organic layer is separated, washed with brine, dried over sodium sulfate, and the solvent is evaporated. The residue is purified by chromatography, with ethyl acetate/cyclohexane (2:1) as a solvent. Thus, 3.9 g N-(4-Cyano-1-dimethylamino-piperidin-4-yl)-N-hydroxy-2-(2,4,6-trimethyl-phenyl)-acetamide is obtained. 1H-NMR (CDCl3): 8.18 ppm (s, broad, 1H), 6.86 ppm (s, 2H), 3.81 ppm (s, 2H), 2.97 ppm (m, 2H), 2.72 ppm (m, 2H), 2.52 ppm (m, 2H), 2.40 ppm (s, 6H), 2.25 ppm (s, 3H), 2.21 ppm (s, 6H), 2.12 ppm (m, 2H).

1. temperatureto warm to room temperature
2. extractionthree times extracted with ethyl acetate
3. customThe organic layer is separated
4. washwashed with brine
5. dry with materialdried over sodium sulfate
6. customthe solvent is evaporated
7. customThe residue is purified by chromatography, with ethyl acetate/cyclohexane (2:1) as a solvent