Lithium hydroxide, monohydrate → 2-Carboxy-4-oxo-7-methylquinoline

HRID 6679Notes

Reaction equation

HRID 6679 reaction equation
C[O:2][C:3]([C:5]1[CH2:14][C:13](=[O:15])[C:12]2[C:7](=[C:8](Cl)[C:9]([CH3:17])=[C:10](Cl)[CH:11]=2)[N:6]=1)=[O:4].O[Li].O>CO.O.[Pd]>[C:3]([C:5]1[CH2:14][C:13](=[O:15])[C:12]2[C:7](=[CH:8][C:9]([CH3:17])=[CH:10][CH:11]=2)[N:6]=1)([OH:4])=[O:2]

Participants

6

Reactant 2

HCID 168937Lithium hydroxide, monohydrateHCID 684344222-(Methoxycarbonyl)-4-oxo-6,8-dichloro-7-methylquinoline

Product 1

HCID 684370112-Carboxy-4-oxo-7-methylquinolineYield 98.8%

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 887MethanolSolventHCID 962WaterSolvent

Procedure

2-(Methoxycarbonyl)-4-oxo-6,8-dichloro-7-methylquinoline (28.5 g, 99.6 mmol) was suspended in methanol (1 L) and a solution of LiOH.H2O (20.5 g, 0.5 mol) in water (200 mL) was added to the solution. The resulting reaction mixture was stirred at ambient temperature for 0.5 hours. Pd/C (5.8 g) was added to the reaction mixture and the resulting reaction mixture was shaken under 50 Psi hydrogen overnight. The reaction mixture was filtered, concentrated under reduced pressure to remove methanol, diluted with water (300 mL) and the pH was adjusted to between pH 3 and pH 4 by 2N HCl. The precipitate was collected by filtration, washed with water and dried to afford a white solid, 2-carboxy-4-oxo-7-methylquinoline (20 g, 90%); NMR (DMSO-d6) 2.40 (s, 3), 6.60 (s, 1), 7.20 (d, 1), 7.68 (s, 1), 7.96 (d, 1) ppm.

Workup

  1. customThe resulting reaction mixture
  2. customthe resulting reaction mixture
  3. filtrationThe reaction mixture was filtered
  4. concentrationconcentrated under reduced pressure
  5. customto remove methanol
  6. additiondiluted with water (300 mL)
  7. filtrationThe precipitate was collected by filtration
  8. washwashed with water
  9. customdried

Sources & evidence

ORD record
ord-05ad1be005714557ad95a163c097a8c8
Source dataset
uspto-grants-2006_08
Patent number
US07084142B2

Reaction notes

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