反応 #2270176

反応方程式

tert-butyl (3R)-6-cyclohexyl-3-(3-{[4-(4-pyridinyl)-1-piperidinyl]carbonyl}-1,2,4-oxadiazol-5-yl)hexanoate

trifluoroacetic acid

→

title compound

収率 92.2%

(3R)-6-Cyclohexyl-3-(3-{[4-(4-pyridinyl)-1-piperidinyl]carbonyl}-1,2,4-oxadiazol-5-yl)hexanoic Acid

収率 92.2%

溶媒

dichloromethane

反応条件

後処理

1. 1
   その他The solvent was removed under reduced pressure
2. 2
   その他the residue azeotroped from toluene (×3)
3. 3
   workup.ADDITIONA saturated solution of sodium carbonate was added to the residue until a pH of 12
4. 4
   workup.ADDITIONwas achieved followed by dropwise addition of an aqueous citric acid solution solution (10% w/v) until the pH
5. 5
   workup.ADDITIONThe solution was then diluted with water
6. 6
   抽出extracted with ethyl acetate (×3)
7. 7
   洗浄The combined organic layers were washed with brine
8. 8
   乾燥dried over anhydrous sodium sulphate
9. 9
   ろ過filtered
10. 10
    その他the solvent removed under reduced pressure

実験手順

A solution of tert-butyl (3R)-6-cyclohexyl-3-(3-{[4-(4-pyridinyl)-1-piperidinyl]carbonyl}-1,2,4-oxadiazol-5-yl)hexanoate (Preparation 31) (376 mg, 0.74 mmol) in dichloromethane (15 ml) was cooled to 0° C. and treated with trifluoroacetic acid (5 ml). The resulting mixture was stirred for 3 hours being allowed to warm to room temperature over this time. The solvent was removed under reduced pressure and the residue azeotroped from toluene (×3) then dichloromethane. A saturated solution of sodium carbonate was added to the residue until a pH of 12 was achieved followed by dropwise addition of an aqueous citric acid solution solution (10% w/v) until the pH became 3.5. The solution was then diluted with water and extracted with ethyl acetate (×3). The combined organic layers were washed with brine, dried over anhydrous sodium sulphate, filtered and the solvent removed under reduced pressure to afford the title compound as a white solid (310 mg).

出典