反応 #67704

反応方程式

trans-(4-Amino-tetrahydro-pyran-3-yl)-carbamic acid tert-butyl ester

intermediate G

trans-(4-Amino-tetrahydro-pyran-3-yl)-carbamic acid tert-butyl ester

Acetic acid

cyclopentanone

Sodium cyanoborohydride

→

title compound

収率 62.0%

trans-(4-Cyclopentylamino-tetrahydro-pyran-3-yl)-carbamic acid tert-butyl ester

収率 62.0%

溶媒

methanol

反応条件

後処理

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITwas continued at 45° C. for 2 h
3. 3
   抽出The mixture was extracted with 2N sodium carbonate solution and ethyl acetate
4. 4
   その他The combined organic phases were dried on sodium sulfate
5. 5
   ろ過filtered
6. 6
   その他evaporated
7. 7
   その他Purification of the residue by flash chromatography on silica gel (dichloromethane/methanol/ammonia 100:0:0→90:10:1)

実験手順

trans-(4-Amino-tetrahydro-pyran-3-yl)-carbamic acid tert-butyl ester (intermediate G, 1.0 g, 4.63 mmol) was dissolved in 90 mL methanol. Acetic acid (1.4 g, 23 mmol) and cyclopentanone (1.18 g, 14 mmol) were added and the reaction mixture was stirred at 45° C. overnight. Sodium cyanoborohydride (612 mg, 9.7 mmol) was added and stirring was continued at 45° C. for 2 h. The mixture was extracted with 2N sodium carbonate solution and ethyl acetate. The combined organic phases were dried on sodium sulfate, filtered and evaporated. Purification of the residue by flash chromatography on silica gel (dichloromethane/methanol/ammonia 100:0:0→90:10:1) yielded the title compound as a yellow solid (815 mg, 62%), MS: m/e=229.4 [(M-butene)+].

出典