Reaction #70239

Reaction equation

3′-fluoro-4′-hydroxyacetophenone

O-(4-nitrobenzyl)hydroxylamine hydrochloride

pyridine

→

3′-fluoro-4′-hydroxyacetophenone-O-4-nitrobenzyloxime

Solvents

ethanol

Conditions

Workup

1. 1
   ConcentrationThe solution was concentrated to a pale yellow oil which
2. 2
   workup.ADDITIONwas diluted with dichloromethane/water
3. 3
   ExtractionThe resultant mixture was extracted with dichloromethane (×3)
4. 4
   WashThe combined organic phases were washed with water and brine
5. 5
   Dryingdried over magnesium sulphate
6. 6
   Filtrationfiltered
7. 7
   Concentrationconcentrated to an off-white solid
8. 8
   OtherThe crude product was purified by column chromatography (SiO2)
9. 9
   Washeluting with 8:2 petrol/ethyl acetate

Procedure

A solution of 3′-fluoro-4′-hydroxyacetophenone (0.063 g, 0.411 mmol), O-(4-nitrobenzyl)hydroxylamine hydrochloride (0.100 g, 0.491 mmol) and pyridine (0.13 ml, 1.61 mmol) in ethanol (5 ml) was stirred at reflux under nitrogen for 5h and cooled to room temperature. The solution was concentrated to a pale yellow oil which was diluted with dichloromethane/water. The resultant mixture was extracted with dichloromethane (×3). The combined organic phases were washed with water and brine, dried over magnesium sulphate, filtered and concentrated to an off-white solid. The crude product was purified by column chromatography (SiO2), eluting with 8:2 petrol/ethyl acetate, to give a 3′-fluoro-4′-hydroxyacetophenone-O-4-nitrobenzyloxime (CP9-132) as light yellow solid (0.081 g, 65%),

Source