Water → HCID 178516197, compound

HRID 2379391Notes

Reaction equation

HRID 2379391 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[N:9]=[N:10][C:11]([Cl:15])=[CH:12][C:13]=2Cl)=[CH:4][CH:3]=1.[OH2:16].[OH-].[Na+]>O1CCOCC1>[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[N:9]=[N:10][C:11]([Cl:15])=[CH:12][C:13]=2[OH:16])=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 962WaterHCID 14798Sodium HydroxideHCID 18956926HCID 18956926, compound

Product 1

HCID 178516197HCID 178516197, compoundYield 67.5%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

3-(4'-Fluorophenyl)-4,6-dichloropyridazine (145.84 g, 0.600 mol) was dissolved in dioxane (800 ml) at 60° C., water (300 ml) was added, and the solution was refluxed. Sodium hydroxide solution (48 g of solid NaOH, dissolved in 300 ml of water) was then added dropwise in the course of half an hour, and the mixture was kept under reflux for a further 5 hours. The mixture was then evaporated to dryness in vacuo, the residue was dissolved in hot water (5 l), insoluble particles were filtered off, and the solution was brought to pH 1 using concentrated hydrochloric acid. The solid obtained was isolated, washed with water and dissolved in dilute ammonia (8 l of water, pH 9-10) for further purification. Small amounts of 3-(4'-fluorophenyl)-4-chloro-6-pyridazinone were then selectively precipitated by carefully adding hydrochloric acid and then removed (by filtration), and the main bulk was then precipitated out (up to pH 1). The solid product obtained was isolated, washed with water and dried to constant weight. 91.0 g (0.4051 mol) of 3-(4'-fluorophenyl)-4-hydroxy-6-chloropyridazine of m.p.=254°-260° C. (point of decomposition) were obtained, which corresponds to a yield of 67.5% of theory.

Workup

  1. temperaturethe solution was refluxed
  2. temperatureunder reflux for a further 5 hours
  3. customThe mixture was then evaporated to dryness in vacuo
  4. dissolutionthe residue was dissolved in hot water (5 l)
  5. filtrationinsoluble particles were filtered off
  6. customThe solid obtained
  7. customwas isolated
  8. washwashed with water
  9. dissolutiondissolved in dilute ammonia (8 l of water, pH 9-10) for further purification
  10. customSmall amounts of 3-(4'-fluorophenyl)-4-chloro-6-pyridazinone were then selectively precipitated by carefully adding hydrochloric acid
  11. customremoved
  12. filtration(by filtration)
  13. customthe main bulk was then precipitated out (up to pH 1)
  14. customThe solid product obtained
  15. customwas isolated
  16. washwashed with water
  17. customdried to constant weight

Sources & evidence

ORD record
ord-77feba260da343028fb1ea6cd29f238f
Source dataset
uspto-grants-1994_11
Patent number
US05362708

Reaction notes

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