Hydrochloric Acid → 5-Methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic acid

HRID 1915448Notes

Reaction equation

HRID 1915448 reaction equation
[CH3:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:3]=1[C:4](=[O:17])[C:5]([C:12]([O:14]CC)=[O:13])=[CH:6][NH:7]2.[OH-].[Na+].Cl>>[CH3:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:3]=1[C:4](=[O:17])[C:5]([C:12]([OH:14])=[O:13])=[CH:6][NH:7]2

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 21829729Ethyl 4-hydroxy-5-methylquinoline-3-carboxylate

Product 1

HCID 156185565-Methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic acidYield 34%

Procedure

Ethyl 5-methyl-4-oxo-1H-quinoline-3-carboxylate (142 mg, 0.61 mmol) was suspended in an aqueous solution of NaOH (1.54 mL of 4% w/v, 1.54 mmol) and the reaction was stirred under reflux for 2 h. After cooling, the reaction mixture was acidified with conc. HCl. The resulting precipitate was collected via filtration, washed with water and dried to yield 5-methyl-4-oxo-1H-quinoline-3-carboxylic acid (42 mg, 34%). 1H NMR (400 MHz, DMSO-d6) δ 15.69 (brs, 1H), 13.81 (brs, 1H), 8.68 (d, J=6.4 Hz, 1H), 7.70-7.64 (m, 2H), 7.27 (d, J=6.4 Hz, 1H), 2.84 (s, 3H). MS (ESI) m/z: 202.2 [M−H]−.

Workup

  1. temperatureunder reflux for 2 h
  2. temperatureAfter cooling
  3. filtrationThe resulting precipitate was collected via filtration
  4. washwashed with water
  5. customdried

Sources & evidence

ORD record
ord-5578a1b1136347d18d897da7eba87e49
Source dataset
uspto-grants-2013_12
Patent number
US08614327B2

Reaction notes

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