反応 #2122494

反応方程式

Acetyl chloride

methanol

4-hydroxy-1-methoxypiperidine-4-carbonitrile

methanol

→

4-Hydroxy-1-methoxy-piperidine-4-carboxylic acid methyl ester

反応条件

後処理

1. 1
   workup.ADDITIONAfter the addition
2. 2
   その他The cooling was removed
3. 3
   その他the suspension formed
4. 4
   workup.WAITwas left
5. 5
   workup.STIRRINGstirring at room temperature overnight
6. 6
   その他The solvent was evaporated under vacuum
7. 7
   workup.DISSOLUTIONthe residue was dissolved in cold (0° C.) water
8. 8
   workup.ADDITIONNaHCO3 (saturated aqueous solution) was added carefully
9. 9
   抽出The aqueous phase was thoroughly extracted three times with ethyl acetate
10. 10
    乾燥dried over magnesium sulfate
11. 11
    ろ過filtered
12. 12
    濃縮concentrated
13. 13
    その他The crude product was used without further purification

実験手順

Acetyl chloride (40.7 g, 0.52 mol) was added slowly to dry methanol (115 ml) cooled to 0° C. under argon. After the addition, the solution was stirred for an additional ½ hour at 0° C. This solution was then added dropwise into a cold (0° C.) solution of 4-hydroxy-1-methoxypiperidine-4-carbonitrile (5.40 g, 34.6 mmol) in methanol (45 ml). The cooling was removed and the suspension formed was left stirring at room temperature overnight. The solvent was evaporated under vacuum and the residue was dissolved in cold (0° C.) water. NaHCO3 (saturated aqueous solution) was added carefully to adjust the pH to 7. The aqueous phase was thoroughly extracted three times with ethyl acetate. The organic layers were combined, dried over magnesium sulfate, filtered and concentrated. The crude product was used without further purification. Yield: 4.9 g of 4-hydroxy-1-methoxy-piperidine-4-carboxylic acid methyl ester (title compound P4.4) as light yellow oil.

出典