Hydroxyamine hydrochloride → 5-(2,4-Dichloro-5-fluorophenyl)-isoxazole

HRID 981343

Reaction equation

HRID 981343 reaction equation
[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[C:5]([F:9])=[CH:4][C:3]=1[C:10]([CH:12]=[CH:13]Cl)=[O:11].Cl.[NH2:16]O>CO>[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[C:5]([F:9])=[CH:4][C:3]=1[C:10]1[O:11][N:16]=[CH:13][CH:12]=1

Participants

4

Reactant 2

HCID 443297Hydroxyamine hydrochlorideHCID 542986662-Chlorovinyl 2,4-dichloro5-fluoro-phenyl ketone

Product 1

HCID 136307205-(2,4-Dichloro-5-fluorophenyl)-isoxazole

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A mixture of 57.6 g of 2-chlorovinyl 2,4-dichloro5-fluoro-phenyl ketone, 16.4 g of hydroxylamine hydrochloride and 150 ml of methanol is heated at the boiling point under reflux for 6 hours, a precipitate separating out after about one hour. This is filtered off cold with suction, washed with a little methanol and dried at 50° C. in vacuo. 33.3 g (63.2%) of 5-(2,4-dichloro-5-fluorophenyl)-isoxazole of melting point 112°-113° C., which, according to investigations by NMR spectroscopy, contains about 6 mole % of an isomer, are obtained.

Workup

  1. temperatureis heated at the boiling point
  2. temperatureunder reflux for 6 hours
  3. customa precipitate separating out after about one hour
  4. filtrationThis is filtered off cold with suction
  5. washwashed with a little methanol
  6. customdried at 50° C. in vacuo
  7. customare obtained

Sources & evidence

ORD record
ord-48d09d193d93463f99fe5680eec7afec
Source dataset
uspto-grants-1991_02
Patent number
US04990646

Linked notes

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