Cesium carbonate → HCID 54308619, compound

HRID 1355585Notes

Reaction equation

HRID 1355585 reaction equation
[CH3:1][C:2]([O:5][C:6]([NH:8][C@@H:9]([C:20]([OH:22])=O)[CH2:10][C:11]1[C:19]2[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=2)[NH:13][CH:12]=1)=[O:7])([CH3:4])[CH3:3].C(=O)([O-])[O-].[Cs+].[Cs+].Br[CH:30]([CH3:34])[C:31](=O)[CH3:32].C([O-])(=O)C.[NH4+:39]>C(O)C.CN(C)C=O.C1(C)C(C)=CC=CC=1.C(OCC)(=O)C.O>[CH3:32][C:31]1[N:39]=[C:20]([C@H:9]([NH:8][C:6](=[O:7])[O:5][C:2]([CH3:1])([CH3:3])[CH3:4])[CH2:10][C:11]2[C:19]3[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=3)[NH:13][CH:12]=2)[O:22][C:30]=1[CH3:34]

Participants

10

Reactant 4

HCID 10796Cesium carbonateHCID 131422-Butanone, 3-bromo-HCID 111050N-((tert-Butoxy)carbonyl)-D-tryptophanHCID 517165Ammonium Acetate

Product 1

HCID 54308619HCID 54308619, compoundYield 24.8%

Reagents, catalysts & solvents 5

HCID 702EthanolSolventHCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 7237O-XyleneSolventHCID 8857Ethyl AcetateSolvent2×

Conditions

Temperature
20 °C

Procedure

To a solution of Boc-D-TRP-OH (15 g, 34 mmol) in absolute ethanol (80 ml) was added cesium carbonate (5.5 g, 17 mmol). The mixture was stirred for about one hour at about 20° C. and concentrated under reduced pressure to afford a white powder which was dissolved in dimethylformamide (100 ml) and treated with 3-bromo-2-butanone (3.56 ml, 34 mmol). After stirring for about two hours at about 20° C. the solvent was removed under reduced pressure to afford a suspension which was treated with ethyl acetate. The precipitate (CsBr) was filtered off and the filtrate evaporated to afford an oil which was dissolved in xylene (400 ml). Ammonium acetate (52 g, 680 mmol) was added and the mixture was refluxed for about 45 min. After cooling to about 20° C., water (150 ml) and ethyl acetate (100 ml) were added. After decantation the organic layer was washed with water (100 ml), NaHCO3 10% (2×100 ml) and brine (100 ml), dried over MgSO4 and the solvent evaporated under reduced pressure. The residue was purified by column chromatography on silica gel using ethyl acetate/heptane 1:1 as eluent to afford 3 g of the desired product as a white powder. Melting point: 138-140° C.

Workup

  1. concentrationconcentrated under reduced pressure
  2. customto afford a white powder which
  3. stirringAfter stirring for about two hours at about 20° C. the solvent
  4. customwas removed under reduced pressure
  5. customto afford a suspension which
  6. filtrationThe precipitate (CsBr) was filtered off
  7. customthe filtrate evaporated
  8. customto afford an oil which
  9. temperaturethe mixture was refluxed for about 45 min
  10. temperatureAfter cooling to about 20° C.
  11. washAfter decantation the organic layer was washed with water (100 ml), NaHCO3 10% (2×100 ml) and brine (100 ml)
  12. dry with materialdried over MgSO4
  13. customthe solvent evaporated under reduced pressure
  14. customThe residue was purified by column chromatography on silica gel

Sources & evidence

ORD record
ord-23e7996407ab4bd4a099d2dc1c678cd2
Source dataset
uspto-grants-2003_07
Patent number
US06586445B1

Reaction notes

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