تفاعل #87114

معادلة التفاعل

triphenylphosphine

imidazole

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

iodide

→

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

المردود 68.1%

المذيبات

DCM

DCM

ظروف التفاعل

المعالجة

1. 1
   أخرىThe cooling bath was removed
2. 2
   درجة الحرارةAfter the mixture was re-cooled to 0° C.
3. 3
   workup.ADDITIONAfter the addition
4. 4
   أخرىthe cooling bath was removed
5. 5
   درجة الحرارةto warm to ambient temperature
6. 6
   workup.STIRRINGstirred for 1.5 h
7. 7
   ترشيحThe mixture was filtered
8. 8
   تركيزthe filtrate was concentrated
9. 9
   أخرىto remove most of the solvent
10. 10
    workup.ADDITIONMTBE (400 mL) was added to the residue
11. 11
    ترشيحthe mixture was filtered
12. 12
    أخرىto remove triphenylphosphine oxide
13. 13
    تركيزThe filtrate was concentrated
14. 14
    أخرىthe residue was purified by flash column chromatography on silica gel

الإجراء التجريبي

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.

المصدر