反応 #40527

反応方程式

4-Oxo-piperidine-1-carboxylic acid tert-butyl ester

tetrahydrofuran

Sodium hydride

Methyl iodide

→

3,3-dimethyl-4-oxo-piperidine-1-carboxylic acid tert-butyl ester

収率 32.0%

反応条件

後処理

1. 1
   温度to warm to room temperature over several hours
2. 2
   workup.STIRRINGStirring
3. 3
   workup.WAITcontinued over night
4. 4
   その他(12 h)
5. 5
   濃縮The light orange mixture was concentrated under reduced pressure
6. 6
   その他The residue was partitioned between ether and water
7. 7
   抽出The aqueous phase was back-extracted with additional ether
8. 8
   洗浄The combined extracts were washed with water and brine
9. 9
   乾燥dried over sodium sulfate
10. 10
    ろ過filtered
11. 11
    濃縮concentrated to a pale yellow solid
12. 12
    その他The solid was triturated with 4% ethyl acetate in hexanes (50 mL)

実験手順

4-Oxo-piperidine-1-carboxylic acid tert-butyl ester (5 g, 25 mmol) was dissolved in tetrahydrofuran (100 mL) and the resulting solution was cooled to 0° C. Sodium hydride (60% in mineral oil, 2.10 g, 53 mmol) was added to the cooled solution in a single portion, and the resulting cloudy mixture was allowed to stir 10 min. Methyl iodide was subsequently added and the mixture was allowed to warm to room temperature over several hours. Stirring continued over night (12 h). The light orange mixture was concentrated under reduced pressure. The residue was partitioned between ether and water. The aqueous phase was back-extracted with additional ether. The combined extracts were washed with water and brine, dried over sodium sulfate, filtered and concentrated to a pale yellow solid. The solid was triturated with 4% ethyl acetate in hexanes (50 mL) to afford 3,3-dimethyl-4-oxo-piperidine-1-carboxylic acid tert-butyl ester as a cream-colored solid (1.8 g, 32%).

出典