Reaction #90438

Reaction equation

CH2Cl2 EtOAc

triphosgene

1-amino-3-(3,6-dibromo-9H-carbazol-9-yl)propan-2-ol

Et3N

→

white solid

Yield 92.2%

5-((3,6-dibromo-9H-carbazol-9-yl)methyl)oxazolidin-2-one

Yield 92.2%

Solvents

CH2Cl2

CH2Cl2

Conditions

Workup

1. 1
   Temperaturewarmed to room temperature
2. 2
   workup.STIRRINGstirred for 1 hour
3. 3
   OtherCH2Cl2 was removed under vacuum
4. 4
   workup.ADDITIONSaturated NH4Cl (5 mL) and 10 mL EtOAc was added to the residue
5. 5
   workup.STIRRINGstirred for 20 min
6. 6
   OtherThen the aqueous layer was separated
7. 7
   Washthe organic layer was washed with water 2×10 mL
8. 8
   ExtractionThe combined aqueous layers were extracted with EtOAc
9. 9
   Dryingdried over anhydrous Na2SO4
10. 10
    Otherevaporated
11. 11
    Otherto afford the crude product, which

Procedure

A solution of triphosgene (0.0890 g, 0.300 mmol, 0.35 equiv) in 2 mL anhydrous CH2Cl2 was added dropwise to a solution of 1-amino-3-(3,6-dibromo-9H-carbazol-9-yl)propan-2-ol (0.3413 g, 0.857 mmol) and Et3N (0.1909 g, 1.886 mmol) in 1 mL CH2Cl2 under N2 atmosphere at 4° C. The reaction mixture was stirred for 15 min at 4° C. and then warmed to room temperature and stirred for 1 hour. CH2Cl2 was removed under vacuum. Saturated NH4Cl (5 mL) and 10 mL EtOAc was added to the residue and stirred for 20 min. Then the aqueous layer was separated and the organic layer was washed with water 2×10 mL. The combined aqueous layers were extracted with EtOAc, dried over anhydrous Na2SO4 and evaporated to afford the crude product, which was subjected to silica gel chromatography using CH2Cl2/EtOAc to afford 0.1173 g white solid, yield 20.0% over 2 steps.

Source