Phenylhydrazine hydrochloride → ethyl 2,3,4,9-tetrahydro-1h-carbazole-3-carboxylate

HRID 1593636Notes

Reaction equation

HRID 1593636 reaction equation
[CH3:1][CH2:2][O:3][C:4]([CH:6]1[CH2:12][CH2:11][C:9](=O)[CH2:8][CH2:7]1)=[O:5].Cl.[C:14]1([NH:20]N)[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1>C(O)C>[CH2:2]([O:3][C:4]([CH:6]1[CH2:12][C:11]2[C:19]3[C:14](=[CH:15][CH:16]=[CH:17][CH:18]=3)[NH:20][C:9]=2[CH2:8][CH2:7]1)=[O:5])[CH3:1]

Participants

4

Reactant 2

HCID 60962Phenylhydrazine hydrochlorideHCID 317638Ethyl 4-oxocyclohexanecarboxylate

Product 1

HCID 282360ethyl 2,3,4,9-tetrahydro-1h-carbazole-3-carboxylateYield 102%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

4-Cyclohexanonecarboxylic acid ethyl ester (25 g, 147 mmol) and phenylhydrazine hydrochloride (20 g, 139 mmol) were refluxed in 550 mL of anhydrous ethanol overnight. The reaction was cooled and concentrated in vacuo. The residue was partitioned between ethyl acetate and water, then the organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo. Purification by flash chromatography on silica gel afforded 34.5 g (96%) of the title compound.

Workup

  1. temperatureThe reaction was cooled
  2. concentrationconcentrated in vacuo
  3. customThe residue was partitioned between ethyl acetate and water
  4. dry with materialthe organic layer was dried over sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customPurification by flash chromatography on silica gel

Sources & evidence

ORD record
ord-2985e539e9de4079bb0e20fd949daaa1
Source dataset
uspto-grants-2007_11
Patent number
US07297704B2

Reaction notes

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