Potassium Hydroxide → 1-amino-4-hydroxyquinolin-2(1H)-one

HRID 1444664Notes

Reaction equation

HRID 1444664 reaction equation
[OH-].[K+].[OH:3][C:4]1[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[N:7]([N:14]=CC2C=CC=CC=2)[C:6](=[O:22])[C:5]=1C(OCC)=O>O1CCOCC1>[NH2:14][N:7]1[C:8]2[C:13](=[CH:12][CH:11]=[CH:10][CH:9]=2)[C:4]([OH:3])=[CH:5][C:6]1=[O:22]

Participants

4

Reactant 2

HCID 14797Potassium HydroxideHCID 67063863Ethyl 4-hydroxy-2-oxo-1-{[phenylmethylene]amino}-1,2-dihydroquinoline-3-carboxylate

Product 1

HCID 591688071-amino-4-hydroxyquinolin-2(1H)-oneYield 91%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

To a solution of 25% by weight aqueous potassium hydroxide (200 mL) and 1,4-dioxane (50 mL) heated to 90-100° C. was added portion wise ethyl 4-hydroxy-2-oxo-1-{[phenylmethylene]amino}-1,2-dihydroquinoline-3-carboxylate (6.72 g, 20.0 mmol). The reaction mixture was heated at reflux for 90 minutes allowing distillation to occur and additional water and dioxane (30 mL each) were added to the reaction vessel to reach the original volume. The mixture was refluxed for an additional 90 minutes with distillation, cooled, washed with 200 mL of 1:1 diethyl ether/ethyl acetate, acidified with concentrated hydrochloric acid to pH 2 and the resulting solid was collected by filtration, washed with water and dried to constant mass to give 1-amino-4-hydroxyquinolin-2(1H)-one as a tan sold (3.22 g, 91% yield), MS (DCI) m/z 177 (M+H)+. 1H NMR (300 MHz, DMSO-d6) δ 5.56 (s, 2H) 5.94 (s, 1H) 7.20 (t, J=7.54 Hz, 1H) 7.62 (m, 1H) 7.85 (m, 2H) 11.33 (s, 1H).

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureat reflux for 90 minutes
  3. distillationdistillation
  4. additionadditional water and dioxane (30 mL each) were added to the reaction vessel
  5. temperatureThe mixture was refluxed for an additional 90 minutes with distillation
  6. temperaturecooled
  7. washwashed with 200 mL of 1:1 diethyl ether/ethyl acetate
  8. filtrationthe resulting solid was collected by filtration
  9. washwashed with water
  10. customdried to constant mass

Sources & evidence

ORD record
ord-91069141cd1e4da8aae2b9ec128d86ed
Source dataset
uspto-grants-2010_02
Patent number
US07662958B2

Reaction notes

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