Hydrogen Peroxide → 3-Chloro-2-fluorobenzoic acid

Temperature

50 °C

3-Chloro-2-fluorobenzaldehyde (15.9 g, 0.1 mol) was dissolved in tert-butanol (60 ml), stirred and heated under N2 at 50° C. 2M aqueous NaOH (100 ml, 0.2 mol) was warmed to 50° C. and added to the solution of the aldehyde. Aqueous hydrogen peroxide solution (H2O2, 30%, 70 ml, 0.6 mol) was added over 45 min, maintaining the temperature at 55-60° C. The mixture was stirred and heated under N2 for a further 1 h, cooled and concentrated in vacuo. The residual slurry was filtered. The filtrate was washed with toluene (2×xx ml) and acidified to pH 1 with 5N hydrochloric acid whilst stirring vigorously. The resulting solid was collected by filtration, washed with water and dried in vacuo at 50° C. to give 11.1 g of product, mp 179-181° C.

1. temperaturemaintaining the temperature at 55-60° C
2. stirringThe mixture was stirred
3. temperatureheated under N2 for a further 1 h
4. temperaturecooled
5. concentrationconcentrated in vacuo
6. filtrationThe residual slurry was filtered
7. washThe filtrate was washed with toluene (2×xx ml)
8. stirringwhilst stirring vigorously
9. filtrationThe resulting solid was collected by filtration
10. washwashed with water
11. customdried in vacuo at 50° C.

ORD record

ord-e7f8a5fd191542f397be6c3e003730a7

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08268823B2