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

HRID 601327Notes

Reaction equation

HRID 601327 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 the product of Example 226C (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 the title compound 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, 2 H) 5.94 (s, 1 H) 7.20 (t, J=7.54 Hz, 1 H) 7.62 (m, 1 H) 7.85 (m, 2 H) 11.33 (s, 1 H).

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-93d3ed1968f84efda30c3023bec94e12
Source dataset
uspto-grants-2011_03
Patent number
US07902203B2

Reaction notes

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