Water → 3-(4-Fluorophenyl)propionic acid

Temperature

40 °C

3-(4-Fluorophenyl)propanoic acid was prepared by procedures analogous to those of Example 6 from 4-fluorobenzaldehyde. Oxalyl chloride (25 mL, 36.4 g, 0.287 mol) was added to 20.0 g (0.119 mol) of this acid. The resulting slurry was heated at reflux with stirring for 1 hour. The solution obtained was cooled and the volatile components were removed by evaporation under reduced pressure. Dichloroethane was added and removed by evaporation under reduced pressure. The residue was dissolved in 75 mL of dichloroethane and the solution was added with stirring to a slurry of 16 g of anhydrous aluminum chloride in 75 mL of dichloroethane. The mixture evolved hydrogen chloride and exothermed raising the temperature to about 40° C. It was then heated at reflux with stirring for about 45 min after which it was allowed to cool overnight. Concentrated aqueous hydrochloric acid (100 mL) was then added with stirring, which resulted in a large exotherm. The resulting mixture was diluted with 100 mL of dichloromethane and 250 mL of water and the organic phase was recovered by means of a separatory funnel, washed with 300 mL of 0.5N aqueous sodium hydroxide, dried over sodium sulfate, and concentrated by evaporation under reduced pressure. The residue, which amounted to 16.3 g of cream colored solid melting at 57°-60° C., was the title compound.

1. temperatureThe resulting slurry was heated
2. temperatureat reflux
3. customThe solution obtained
4. temperaturewas cooled
5. customthe volatile components were removed by evaporation under reduced pressure
6. additionDichloroethane was added
7. customremoved by evaporation under reduced pressure
8. dissolutionThe residue was dissolved in 75 mL of dichloroethane
9. additionthe solution was added
10. stirringwith stirring to a slurry of 16 g of anhydrous aluminum chloride in 75 mL of dichloroethane
11. temperatureIt was then heated
12. temperatureat reflux
13. stirringwith stirring for about 45 min after which it
14. temperatureto cool overnight
15. additionConcentrated aqueous hydrochloric acid (100 mL) was then added
16. stirringwith stirring
17. customwhich resulted in a large exotherm
18. customthe organic phase was recovered by means of a separatory funnel
19. washwashed with 300 mL of 0.5N aqueous sodium hydroxide
20. dry with materialdried over sodium sulfate
21. concentrationconcentrated by evaporation under reduced pressure

ORD record

ord-e82bbd2985f54c6b80603ea065a255d6

Source dataset

uspto-grants-1998_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05780465