Sodium Hydroxide → 2,3,4,9-Tetrahydro-1H-carbazol-2-amine

HRID 1593626Notes

Reaction equation

HRID 1593626 reaction equation
[CH2:1]1[C:13]2[NH:12][C:11]3[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=3)[C:5]=2[CH2:4][CH2:3][C:2]1=[N:14]O.[OH-].[Na+]>C(O)C>[CH2:1]1[C:13]2[NH:12][C:11]3[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=3)[C:5]=2[CH2:4][CH2:3][CH:2]1[NH2:14]

Participants

4

Reactant 2

HCID 14798Sodium HydroxideHCID 126969424HCID 126969424, compound

Product 1

HCID 205292292,3,4,9-Tetrahydro-1H-carbazol-2-amineYield 77.9%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A suspension of the crude 1,3,4,9-tetrahydrocarbazole-2-one oxime (1.093 g, 5.45 mmol) in ethanol (27.5 mL) was treated while cooling in ice bath with 2.5 N aqueous sodium hydroxide (22 mL). To the stirred dark solution kept under nitrogen was added portionwise over 15 minutes Al—Ni alloy (2.05 g). After 5 minutes the cooling bath was removed and the mixture stirred at room temperature for one hour. The catalysts was filtered off over Celite, the cake quickly washed under nitrogen with a small amount of 1:1 (v/v) ethanol-water and the filtrate was extracted three times with dichloromethane. The combined extracts were washed with water and brine and dried over anhydrous magnesium sulfate. Removal of the solvent provided a dark brown foam that crystallized upon standing. The residue was purified by flash chromatography over silica gel Merck 60 using a gradient from 3% to 10% of ammonia saturated methanol in dichloromethane to provide the title amine as a foam (0.791 g). MS (ES): [M+H]+ @m/z 187.1

Workup

  1. additionwas treated
  2. customAfter 5 minutes the cooling bath was removed
  3. filtrationThe catalysts was filtered off over Celite
  4. washthe cake quickly washed under nitrogen with a small amount of 1:1 (v/v) ethanol-water
  5. extractionthe filtrate was extracted three times with dichloromethane
  6. washThe combined extracts were washed with water and brine
  7. dry with materialdried over anhydrous magnesium sulfate
  8. customRemoval of the solvent
  9. customprovided a dark brown foam that
  10. customcrystallized
  11. customThe residue was purified by flash chromatography over silica gel Merck 60 using a gradient from 3% to 10% of ammonia saturated methanol in dichloromethane

Sources & evidence

ORD record
ord-dc34d1bf805a454e9f622f1abd55ab7b
Source dataset
uspto-grants-2007_11
Patent number
US07297704B2

Reaction notes

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