3-Hydroxybenzoic Acid → 4-Bromo-3-hydroxybenzoic acid

This acid was prepared in similar way to that described by Buehler et al (Buehler, C. A., Harris, J. O., Shacklett, C and Block, B. P.; J. Am. Chem. Soc., 68, 574-577 (1946)). To a stirred suspension of 3-hydroxybenzoic acid (50.0 g, 0.362 mol) in acetic acid (495 ml), at RT under argon, was added a solution of bromine (57.97 g, 0.3627 mol) in acetic acid (192 ml) over 2 h. During the addition the internal temperature rose from 18.0 to 22.0° C. The mixture was stirred for 21 h and then concentrated under vacuum, where approximately (500 ml) of distillate was collected. The resulting concentrated solution was stored at 4° C. for 2 h. The resulting white solid was filtered off and washed with cold water (100 ml). This solid was dissolved in a minimum volume of boiling water (220 ml), filtered and allowed to cool to room temperature. The resulting solid was removed by filtration, washed with cold water and dried in a vacuum oven at 58° C. to give the title compound (12.50 g, yield 15.9%), mp=231-232° C., (lit mp 225-226° C.)1.

1. customThis acid was prepared in similar way to
2. additionDuring the addition the internal temperature
3. customrose from 18.0 to 22.0° C
4. concentrationconcentrated under vacuum, where approximately (500 ml) of distillate
5. customwas collected
6. waitThe resulting concentrated solution was stored at 4° C. for 2 h
7. filtrationThe resulting white solid was filtered off
8. washwashed with cold water (100 ml)
9. dissolutionThis solid was dissolved in a minimum volume of boiling water (220 ml)
10. filtrationfiltered
11. customThe resulting solid was removed by filtration
12. washwashed with cold water
13. customdried in a vacuum oven at 58° C.

ORD record

ord-711399c6fc6345198d0513dab30cb773

Source dataset

uspto-grants-2004_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06787550B1