تفاعل #2122494
ord-ea988b9121424c90ac98a8932766ebc5
معادلة التفاعل
الكواشف
ظروف التفاعل
المعالجة
- 1workup.ADDITIONAfter the addition
- 2أخرىThe cooling was removed
- 3أخرىthe suspension formed
- 4workup.WAITwas left
- 5workup.STIRRINGstirring at room temperature overnight
- 6أخرىThe solvent was evaporated under vacuum
- 7workup.DISSOLUTIONthe residue was dissolved in cold (0° C.) water
- 8workup.ADDITIONNaHCO3 (saturated aqueous solution) was added carefully
- 9استخلاصThe aqueous phase was thoroughly extracted three times with ethyl acetate
- 10تجفيفdried over magnesium sulfate
- 11ترشيحfiltered
- 12تركيزconcentrated
- 13أخرىThe crude product was used without further purification
الإجراء التجريبي
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.