Acetone → 8-methoxycarbonyl-4,4-dimethyl-4H-pyrrolo[2,1-c][1,4]-benzoxazine

HRID 399822Notes

Reaction equation

HRID 399822 reaction equation
[OH:1][C:2]1[CH:11]=[CH:10][C:5]([C:6]([O:8][CH3:9])=[O:7])=[CH:4][C:3]=1[N:12]1[CH:16]=[CH:15][CH:14]=[CH:13]1.[CH3:17][C:18]([CH3:20])=O.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[CH3:9][O:8][C:6]([C:5]1[CH:10]=[CH:11][C:2]2[O:1][C:18]([CH3:20])([CH3:17])[C:13]3=[CH:14][CH:15]=[CH:16][N:12]3[C:3]=2[CH:4]=1)=[O:7]

Participants

5

Reactant 3

HCID 180AcetoneHCID 6101p-Toluenesulfonic acidHCID 18945287Methyl 4-hydroxy-3-(pyrrol-1-yl)benzoate

Product 1

HCID 189453208-methoxycarbonyl-4,4-dimethyl-4H-pyrrolo[2,1-c][1,4]-benzoxazine

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

The mixture of methyl 4-hydroxy-3-(pyrrol-1-yl)benzoate (4.0 g), acetone (40 ml) and p-toluenesulfonic acid (0.8 g) in toluene (80 ml) was heated under reflux for 15 hours under stirring. The solvent was removed by evaporation and to the residue was added a mixture of ethyl acetate and water. The mixture was adjusted to pH 8 with potassium carbonate and the separated organic layer was washed with brine, dried over magnesium sulfate and evaporated in vacuo. The residue was purified by column chromatography on silica gel eluting with a mixture of toluene and n-hexane (1:1, V/V). The eluted fractions containing the desired product were collected and evaporated in vacuo. The residue was triturated with a mixture of diisopropyl ether and n-hexane to give 8-methoxycarbonyl-4,4-dimethyl-4H-pyrrolo[2,1-c][1,4]-benzoxazine.

Workup

  1. temperaturewas heated
  2. temperatureunder reflux for 15 hours
  3. customThe solvent was removed by evaporation and to the residue
  4. additionwas added
  5. additiona mixture of ethyl acetate and water
  6. washthe separated organic layer was washed with brine
  7. dry with materialdried over magnesium sulfate
  8. customevaporated in vacuo
  9. customThe residue was purified by column chromatography on silica gel eluting with a mixture of toluene and n-hexane (1:1, V/V)
  10. additionThe eluted fractions containing the desired product
  11. customwere collected
  12. customevaporated in vacuo
  13. customThe residue was triturated with a mixture of diisopropyl ether and n-hexane

Sources & evidence

ORD record
ord-f79872bba1a44d9db3ecfdd1751384c0
Source dataset
uspto-grants-1998_10
Patent number
US05824691

Reaction notes

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