3-Methyl-2-butanone → 2,3,3-Trimethyl-3H-indole-5-carboxylic acid

HRID 1184952Notes

Reaction equation

HRID 1184952 reaction equation
[NH:1]([C:3]1[CH:11]=[CH:10][C:6]([C:7]([OH:9])=[O:8])=[CH:5][CH:4]=1)N.[CH:12]([C:15]([CH3:17])=O)([CH3:14])[CH3:13]>C(O)(=O)C>[CH3:17][C:15]1[C:12]([CH3:14])([CH3:13])[C:11]2[C:3](=[CH:4][CH:5]=[C:6]([C:7]([OH:9])=[O:8])[CH:10]=2)[N:1]=1

Participants

4

Reactant 2

HCID 112513-Methyl-2-butanoneHCID 120894-Hydrazinobenzoic acid

Product 1

HCID 30196962,3,3-Trimethyl-3H-indole-5-carboxylic acidYield 80.1%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

A solution of 4-hydrazinobenzoic acid (10.0 g, 65.7 mmol), isopropylmethylketone (21.1 mL, 197 mmol) in acetic acid (35 mL) was heated under reflux in an oil bath for 20 h. After cooling to ambient temperature the solvent was evaporated off under reduced pressure and to it was added a saturated aqueous solution of NaHCO3 (50 mL) and washed with CH2Cl2 (3×40 mL). The pH of the aqueous solution was adjusted with 1 M aqueous HCl to ca. 2, and then extracted with CH2Cl2 (3×50 mL). The combined organic solution was then dried with Na2SO4, filtered and concentrated to dryness under reduced pressure to yield the desired product (10.7 g, 80%) as a brownish solid.

Workup

  1. temperatureunder reflux in an oil bath for 20 h
  2. customwas evaporated off under reduced pressure and to it
  3. additionwas added a saturated aqueous solution of NaHCO3 (50 mL)
  4. washwashed with CH2Cl2 (3×40 mL)
  5. extractionextracted with CH2Cl2 (3×50 mL)
  6. dry with materialThe combined organic solution was then dried with Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated to dryness under reduced pressure

Sources & evidence

ORD record
ord-a05d828c2a3f4e48a88fd59c9f726e2c
Source dataset
uspto-grants-2014_03
Patent number
US08669374B2

Reaction notes

Loading…