反应详情

温度

20 °C

To a solution of tert-butyl 2,4-dioxopiperidine-1-carboxylate (Ark Pharm, Inc., Libertyville, Ill.; 2.0 g, 9.389 mmol) in THF (1 L) at 20° C. was added LHMDS (1.0M in THF; 23.47 mL, 23.47 mmol) (dropwise), and the resulting mixture was stirred at 20° C. for 30 min. Isobutyl iodide (6.9 g, 37.55 mmol) was added, and the resulting mixture was stirred at 20° C. for 1 h. The mixture was neutralized with 10M aq. KHSO4 solution and extracted with EtOAc. The organic extract was dried over Na2SO4, filtered, and concentrated in vacuo to provide crude rac-tert-butyl 5-isobutyl-2,4-dioxopiperidine-1-carboxylate (0.75 g) (used without further purification in subsequent transformations): m/z (ESI, +ve) 170.0 [(M+H)-100]+.

1. stirringthe resulting mixture was stirred at 20° C. for 1 h
2. extractionextracted with EtOAc
3. extractionThe organic extract
4. dry with materialwas dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo