反应详情

温度

0 °C

To a slurry of tert-butyl 3-oxopiperazine-1-carboxylate (10 g, 49.9 mmol) in 250 mL of DMF, NaH (60% in mineral oil) (2.1 g, 52.4 mmol) was added in portions. The mixture was stirred for 15 min after completion of addition, cooled to 0° C. and iodoethane (5.62 mL, 69.92 mmol) slowly added over ˜3 min. The resultant suspension was stirred at rt for 2 h. Water was slowly added (400 mL) and then 250 mL of 1:1 ethyl acetate:diethyl ether. The layers were separated and then the organic phase was washed with brine, dried over sodium sulfate, filtered and concentrated to afford tert-butyl 4-ethyl-3-oxopiperazine-1-carboxylate as a colorless oil weighing 6.4 g which was used directly in the next step.

1. additionafter completion of addition
2. customThe layers were separated
3. washthe organic phase was washed with brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated