Benzene → 2-Benzoyl-4-bromobenzoic acid

Temperature

5 °C

A mixture of benzene (2.94 ml), o-dichlorobenzene (20 ml) and aluminum chloride (5.87 g) was cooled to 5° C. and 5-bromophthalic anhydride (5.0 g) was added by small portions while maintaining the temperature of the mixture below 10° C. The mixture was stirred at around 25° C. for 1 h and then at 80° C. for 1 h. The reaction mixture was cooled to around 5° C. and ethyl acetate (40 ml) was added dropwise. Water (20 ml) was added dropwise below 40° C. The organic layer was separated and 4N hydrochloric acid (20 ml) was added. The mixture was stirred until the precipitated solid was dissolved. The organic layer was separated and washed with water (20 ml). The solvent was evaporated and toluene (30 ml) and ethyl acetate (3 ml) were added to the residue, which was followed by heating to 80° C. The obtained solution was cooled to 25° C. over 30 min and the precipitated crystals were collected by filtration. The crystals were dissolved in a mixture of toluene (30 ml) and ethyl acetate (1.5 ml) by heating and the obtained solution was cooled to 25° C. and then to 5° C. The precipitated crystals were collected by filtration and washed with toluene, to give the title compound (2.81 g, yield 41.8%).

1. temperaturewhile maintaining the temperature of the mixture below 10° C
2. waitat 80° C. for 1 h
3. temperatureThe reaction mixture was cooled to around 5° C.
4. customThe organic layer was separated
5. addition4N hydrochloric acid (20 ml) was added
6. stirringThe mixture was stirred until the precipitated solid
7. dissolutionwas dissolved
8. customThe organic layer was separated
9. washwashed with water (20 ml)
10. customThe solvent was evaporated
11. additiontoluene (30 ml) and ethyl acetate (3 ml) were added to the residue, which
12. temperatureby heating to 80° C
13. temperatureThe obtained solution was cooled to 25° C. over 30 min
14. filtrationthe precipitated crystals were collected by filtration
15. dissolutionThe crystals were dissolved in a mixture of toluene (30 ml) and ethyl acetate (1.5 ml)
16. temperatureby heating
17. temperaturethe obtained solution was cooled to 25° C.
18. customto 5° C
19. filtrationThe precipitated crystals were collected by filtration
20. washwashed with toluene

ORD record

ord-193d063c4e2844f2a4706a4ef598d142

Source dataset

uspto-grants-2006_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07034039B2