Pyridine → 3'-Fluoro-4'-methoxyacetophenone-o-4-nitrobenzyloxime

HRID 41957

Reaction equation

HRID 41957 reaction equation
[CH3:1][C:2]([C:4]1[CH:9]=[CH:8][C:7]([O:10][CH3:11])=[C:6]([F:12])[CH:5]=1)=O.Cl.[N+:14]([C:17]1[CH:25]=[CH:24][C:20]([CH2:21][O:22][NH2:23])=[CH:19][CH:18]=1)([O-:16])=[O:15].N1C=CC=CC=1>C(O)C>[N+:14]([C:17]1[CH:18]=[CH:19][C:20]([CH2:21][O:22][N:23]=[C:2]([C:4]2[CH:9]=[CH:8][C:7]([O:10][CH3:11])=[C:6]([F:12])[CH:5]=2)[CH3:1])=[CH:24][CH:25]=1)([O-:16])=[O:15]

Participants

5

Reactant 3

HCID 1049PyridineHCID 74967Hydroxylamine, O-((4-nitrophenyl)methyl)-, hydrochloride (1:1)HCID 968281-(3-Fluoro-4-methoxyphenyl)ethan-1-one

Product 1

HCID 871386353'-Fluoro-4'-methoxyacetophenone-o-4-nitrobenzyloximeYield 65.3%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of 3-fluoro-4-methoxyacetophenone (0.064 g, 0.380 mmol), O-(4-nitrobenzyl)hydroxylamine hydrochloride (0.111 g, 0.552 mmol) and pyridine (0.14 ml, 1.73 mmol) in ethanol (7 ml) was stirred at reflux under nitrogen for 4 h and cooled to room temperature. The solution was concentrated to a yellow oil which was diluted with water/dichloromethane. The suspension was extracted with dichloromethane (×3). The combined organic phases were washed with water and brine, dried over magnesium sulphate, filtered and concentrated to a yellow oil. The crude product was purified by column chromatography (SiO2), eluting with 9:1 petrol/ethyl acetate, to give a yellow oil which was triturated with petrol, and the resultant off white solid was further washed with petrol to give 3′-fluoro-4′-methoxyacetophenone-O-4-nitrobenzyloxime (CP9-123) as a white solid (0.079 g, 65%), m.p. 67-68°.

Workup

  1. temperatureat reflux under nitrogen for 4 h
  2. concentrationThe solution was concentrated to a yellow oil which
  3. additionwas diluted with water/dichloromethane
  4. extractionThe suspension was extracted with dichloromethane (×3)
  5. washThe combined organic phases were washed with water and brine
  6. dry with materialdried over magnesium sulphate
  7. filtrationfiltered
  8. concentrationconcentrated to a yellow oil
  9. customThe crude product was purified by column chromatography (SiO2)
  10. washeluting with 9:1 petrol/ethyl acetate
  11. customto give a yellow oil which
  12. customwas triturated with petrol
  13. washthe resultant off white solid was further washed with petrol

Sources & evidence

ORD record
ord-243c121923ed424e806a9e99f8b91e83
Source dataset
uspto-grants-2013_09
Patent number
US08536157B2

Linked notes

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