反応 #2122492

反応方程式

3-[1-Methoxy-4-(4-methoxy-benzylsulfanyl)-piperidin-4-yl]-3-oxo-2-(2,4,6-trimethylphenyl)-propionic acid methyl ester

3-[1-methoxy-4-(4-methoxy-benzylsulfanyl)-piperidin-4-yl]-3-oxo-2-(2,4,6-trimethylphenyl)-propionic acid methyl ester

sodium hydroxide

→

4-hydroxy-8-methoxy-3-(2,4,6-trimethyl-phenyl)-1-thia-8-aza-spiro[4.5]dec-3-en-2-one

収率 48.3%

溶媒

water

trifluoroacetic acid

反応条件

後処理

1. 1
   温度heated
2. 2
   温度on reflux for 18 hours
3. 3
   抽出extracted with t-butylmethyl ether
4. 4
   乾燥The organic layer was dried over anhydrous sodium sulfate
5. 5
   その他the solvent evaporated
6. 6
   その他The residue was chromatographed on silica gel with ethyl acetate/cyclohexane (1:1

実験手順

470 mg 3-[1-Methoxy-4-(4-methoxy-benzylsulfanyl)-piperidin-4-yl]-3-oxo-2-(2,4,6-trimethylphenyl)-propionic acid methyl ester (from Step 6) was dissolved in 15 ml trifluoroacetic acid and heated on reflux for 18 hours. The mixture was cooled to room temperature, diluted with water, the pH adjusted to 4.2 by the addition of aqueous sodium hydroxide, then extracted with t-butylmethyl ether. The organic layer was dried over anhydrous sodium sulfate, and the solvent evaporated. The residue was chromatographed on silica gel with ethyl acetate/cyclohexane (1:1, then 2:1) as a solvent, to yield 156 mg 4-hydroxy-8-methoxy-3-(2,4,6-trimethyl-phenyl)-1-thia-8-aza-spiro[4.5]dec-3-en-2-one (compound P2.4) as a solid, mp 67-71° C.

出典