Ethyl Acetate → HCID 15117200, compound

HRID 1029606Notes

Reaction equation

HRID 1029606 reaction equation
[CH2:1]([O:4][C:5]([N:7]1[CH2:11][C@H:10]([O:12][Si:13]([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14])[CH2:9][C@H:8]1[C:20](O)=[O:21])=[O:6])[CH:2]=[CH2:3].[CH:23]1(N=C=NC2CCCCC2)CCCCC1.CC1(C)OC(=O)CC(=O)O1.C(OCC)(=O)C>ClCCl.CN(C)C1C=CN=CC=1>[C:20]([C@@H:8]1[CH2:9][C@@H:10]([O:12][Si:13]([C:16]([CH3:18])([CH3:19])[CH3:17])([CH3:15])[CH3:14])[CH2:11][N:7]1[C:5]([O:4][CH2:1][CH:2]=[CH2:3])=[O:6])(=[O:21])[CH3:23]

Participants

7

Reactant 4

HCID 8857Ethyl AcetateHCID 10868DicyclohexylcarbodiimideHCID 162492,2-Dimethyl-1,3-dioxane-4,6-dioneHCID 15117199HCID 15117199, compound

Product 1

HCID 15117200HCID 15117200, compoundYield 71.1%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent

Procedure

To a solution of (2S,4R)-1-allyloxycarbonyl-4-t-butyldimethylsilyloxy-2-carboxypyrrolidine (15 g) in dichloromethane (150 ml) were added dicyclohexylcarbodiimide (11.5 g), Meldrum's acid (8.0 g) and 4-dimethylaminopyridine (6.8 g) at 0° C. After stirring for 24 hours at ambient temperature, the resulting precipitate was removed by filtration. The filtrate was washed with 1N hydrochloric acid solution, and evaporated in vacuo. The residue was dissolved in a mixture of acetic acid (80 ml) and water (60 ml), and refluxed for 1 hour. Evaporation of the solvent gave a residue, which was taken up into ethyl acetate. The solution was washed in turn with saturated sodium bicarbonate and brine, dried over magnesium sulfate, and evaporated. The residue was dissolved in dimethylformamide (60 ml) and then imidazole (8.7 g) and t-butyldimethylsilyl chloride (8.7 g) were added thereto at ambient temperature. After stirring for 10 hour, the mixture was poured into water (200 ml), extracted with ethyl acetate (100 ml×2), dried over magnesium sulfate and evaporated. The residue was chromatographed on silica gel eluting with a mixture of n-hexane and ethyl acetate (2:1, V/V) to give (2S,4R)-2-acetyl-1-allyloxycarbonyl-4-t-butyldimethylsilyloxypyrrolidine (10.6 g).

Workup

  1. customthe resulting precipitate was removed by filtration
  2. washThe filtrate was washed with 1N hydrochloric acid solution
  3. customevaporated in vacuo
  4. dissolutionThe residue was dissolved in a mixture of acetic acid (80 ml) and water (60 ml)
  5. temperaturerefluxed for 1 hour
  6. customEvaporation of the solvent
  7. customgave a residue, which
  8. washThe solution was washed in turn with saturated sodium bicarbonate and brine
  9. dry with materialdried over magnesium sulfate
  10. customevaporated
  11. dissolutionThe residue was dissolved in dimethylformamide (60 ml)
  12. additionimidazole (8.7 g) and t-butyldimethylsilyl chloride (8.7 g) were added
  13. customat ambient temperature
  14. stirringAfter stirring for 10 hour
  15. additionthe mixture was poured into water (200 ml)
  16. extractionextracted with ethyl acetate (100 ml×2)
  17. dry with materialdried over magnesium sulfate
  18. customevaporated
  19. customThe residue was chromatographed on silica gel eluting with a mixture of n-hexane and ethyl acetate (2:1, V/V)

Sources & evidence

ORD record
ord-dad8b559c3a7439d8a3a54de9ff3de89
Source dataset
uspto-grants-1992_04
Patent number
US05102877

Reaction notes

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