Ammonia → 2-Amino-3-chlorobenzoic acid

Temperature

-70 °C

70 ml of methanol was added to an autoclave, and cooled to −70° C., and 16 g (942 mmol) of a generated ammonia gas was added. 30 g (157 mmol) of 2,3-dichlorobenzoic acid and 0.78 g (7.85 mmol) of copper(I) chloride were added. The autoclave was sealed, and heated in an oil bath at 130° C. and 30 atmospheres for 20 hours. After the completion of the reaction, the autoclave was cooled to room temperature, and the reaction mixture was transferred into a reaction flask. 100 ml of water was added to the reaction solution, and the reaction solution was heated in an oil bath to 100° C. to remove the ammonia and the methanol. Then, the reaction solution was cooled to room temperature, and hydrochloric acid was added to adjust the pH value to 3. The precipitated crystals were filtered and dried to obtain 21.8 g of 2-amino-3-chlorobenzoic acid as white crystals with a yield of 81%.

1. customThe autoclave was sealed
2. temperatureheated in an oil bath at 130° C.
3. customAfter the completion of the reaction
4. temperaturethe autoclave was cooled to room temperature
5. customthe reaction mixture was transferred into a reaction flask
6. temperaturethe reaction solution was heated in an oil bath to 100° C.
7. customto remove the ammonia
8. temperatureThen, the reaction solution was cooled to room temperature
9. additionhydrochloric acid was added
10. filtrationThe precipitated crystals were filtered
11. customdried

ORD record

ord-d28c8cdca0e74ca1a0cc4e05e2a2582f

Source dataset

uspto-grants-2015_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09006477B2