反応 #87114

反応方程式

triphenylphosphine

imidazole

(S)-methyl 2-((tert-butoxycarbonyl)amino)-3-hydroxypropanoate

iodide

→

(R)-methyl 2-((tert-butoxycarbonyl)amino)-3-iodopropanoate

収率 68.1%

溶媒

DCM

DCM

反応条件

後処理

1. 1
   その他The cooling bath was removed
2. 2
   温度After the mixture was re-cooled to 0° C.
3. 3
   workup.ADDITIONAfter the addition
4. 4
   その他the cooling bath was removed
5. 5
   温度to warm to ambient temperature
6. 6
   workup.STIRRINGstirred for 1.5 h
7. 7
   ろ過The mixture was filtered
8. 8
   濃縮the filtrate was concentrated
9. 9
   その他to remove most of the solvent
10. 10
    workup.ADDITIONMTBE (400 mL) was added to the residue
11. 11
    ろ過the mixture was filtered
12. 12
    その他to remove triphenylphosphine oxide
13. 13
    濃縮The filtrate was concentrated
14. 14
    その他the residue was purified by flash column chromatography on silica gel

実験手順

A mixture of triphenylphosphine (131 g, 0.500 mol) and imidazole (34 g, 0.50 mol) in DCM (600 mL) was cooled to 0° C. and iodide (127 g, 0.50 mol) was added in small portions over 0.5 h. The cooling bath was removed and the mixture was stirred for 0.5 h. After the mixture was re-cooled to 0° C., a solution of (S)-methyl 2-((tert-butoxycarbonyl)amino)-3-hydroxypropanoate (73 g, 0.33 mol) in DCM (300 mL) was added dropwise. After the addition, the cooling bath was removed and the mixture was allowed to warm to ambient temperature and stirred for 1.5 h. The mixture was filtered and the filtrate was concentrated to remove most of the solvent. MTBE (400 mL) was added to the residue and the mixture was filtered to remove triphenylphosphine oxide. The filtrate was concentrated and the residue was purified by flash column chromatography on silica gel to afford (R)-methyl 2-((tert-butoxycarbonyl)amino)-3-iodopropanoate (74.0 g, 68% yield) as a colorless solid.

出典