反应 #2122494

反应方程式

Acetyl chloride

methanol

4-hydroxy-1-methoxypiperidine-4-carbonitrile

methanol

→

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

反应条件

后处理

1. 1
   workup.ADDITIONAfter the addition
2. 2
   其他The cooling was removed
3. 3
   其他the suspension formed
4. 4
   workup.WAITwas left
5. 5
   workup.STIRRINGstirring at room temperature overnight
6. 6
   其他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
   萃取The aqueous phase was thoroughly extracted three times with ethyl acetate
10. 10
    干燥dried over magnesium sulfate
11. 11
    过滤filtered
12. 12
    浓缩concentrated
13. 13
    其他The crude product was used without further purification

实验过程

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.

来源