Sulfuric Acid → 1-Benzylazepan-3-one

HRID 1269905Notes

Reaction equation

HRID 1269905 reaction equation
S(=O)(=O)(O)O.[CH2:6]([N:13]1[CH2:19][CH2:18][CH2:17][CH:16](C(OCC)=O)[C:15](=[O:25])[CH2:14]1)[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1.C(N1CCCCC(=O)C1C(OCC)=O)C1C=CC=CC=1.[OH-].[Na+]>C(O)C>[CH2:6]([N:13]1[CH2:19][CH2:18][CH2:17][CH2:16][C:15](=[O:25])[CH2:14]1)[C:7]1[CH:8]=[CH:9][CH:10]=[CH:11][CH:12]=1

Participants

6

Reactant 4

HCID 1118Sulfuric Acid2×HCID 14798Sodium HydroxideHCID 22933378HCID 22933378, compoundHCID 22934086HCID 22934086, compound

Product 1

HCID 151522641-Benzylazepan-3-oneYield 106.6%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Conditions

Temperature
120 °C

Procedure

Under a nitrogen atmosphere, a 75%-aqueous sulfuric acid solution (2 ml) was added to a solution of ethyl 1-benzyl-3-oxoazepane-4-carboxylate (150 mg, 0.545 mmol) in ethanol (1 ml) at room temperature, and the resulting mixture was heated to 120° C. After 3 hours, completion of the reaction was confirmed and the resulting mixture was cooled. On the other hand, under a nitrogen atmosphere, a 75%-aqueous sulfuric acid solution (2 ml) was added to a solution of the mixture containing ethyl 1-benzyl-3-oxoazepane-2-carboxylate (200 mg, content=about 75%) in ethanol (1 ml) at room temperature, and the resulting mixture was heated to 120° C. After 12 hours, completion of the reaction was confirmed and the temperature was lowered. The reaction solution was combined with that obtained above, and the combined reaction solution was poured onto ice and adjusted to pH 8 with a 2M-aqueous sodium hydroxide solution. The combined reaction solution thus treated was extracted with ethyl acetate (50 ml×2) and the organic layer was dried over anhydrous magnesium sulfate. The organic layer dried was concentrated under reduced pressure and the resulting residue was purified by a silica gel column chromatography (eluent: hexane/ethyl acetate) to obtain 1-benzylazepan-3-one (118.1 mg, 53%).

Workup

  1. temperaturethe resulting mixture was cooled
  2. temperaturethe resulting mixture was heated to 120° C
  3. waitAfter 12 hours
  4. customthat obtained above, and
  5. customthe combined reaction solution
  6. additionwas poured onto ice
  7. customThe combined reaction solution
  8. additionthus treated
  9. extractionwas extracted with ethyl acetate (50 ml×2)
  10. dry with materialthe organic layer was dried over anhydrous magnesium sulfate
  11. customThe organic layer dried
  12. concentrationwas concentrated under reduced pressure
  13. customthe resulting residue was purified by a silica gel column chromatography (eluent: hexane/ethyl acetate)

Sources & evidence

ORD record
ord-d362f7cfb4c54764912552d26aaadb4b
Source dataset
uspto-grants-2007_04
Patent number
US07199147B2

Reaction notes

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