3-Hydroxybenzoic Acid → 2-Chloro-3-hydroxybenzoic acid

Chlorine gas (10.3 g; 147 mmol) was slowly bubbled through a cold solution of 20 g (145 mmol) of 3-hydroxy benzoic acid in 100 mL of methanol, under nitrogen, while maintaining the temperature below −60° C. After approximately thirty minutes, the chlorine gas was flushed out with nitrogen and the reaction mixture was allowed to warm to room temperature and diluted with 100 mL of water. The desired titled compound was isolated by recrystallization to provide a white solid. This solid was purified by recrystallization from 50 mL of water followed by recrystallization from 130 mL of benzene containing 10 mL of acetone to provide the desired titled compound.

1. temperaturewhile maintaining the temperature below −60° C
2. waitAfter approximately thirty minutes
3. customthe chlorine gas was flushed out with nitrogen
4. additiondiluted with 100 mL of water

ORD record

ord-fa69917207fd430b845bdfb820130d8a

Source dataset

uspto-grants-2004_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06693199B2