Methanol → 4-Amino-3-chloro-5-methoxyiminomethylbenzoic acid

In a 5-liter three-necked round-bottomed flask was placed 210 g (0.86 moles) of the previously prepared 4-amino-3-chloro-5-methoxyiminomethylbenzoate, 1.7 l of methanol and 462 g (1.73 moles) of 15% aqueous sodium hydroxide. The resulting mixture was refluxed for 3 hours, after which the reaction mixture was stirred overnight at room temperature. The reaction mixture was concentrated using a rotary evaporator. The crude reaction mixture was dissolved in 2 l of water. The resulting aqueous solution was washed once with 500 mL of ethyl acetate, cooled in an ice bath and acidified to pH=2 with concentrated hydrochloric acid. The expected 4-amino-3-chloro-5-methoxyiminomethylbenzoic acid precipitated as a light yellow solid which was separated by suction filtration. The filter cake was washed with a 1:2 mixture of ethyl ether and hexane yielding after drying 185.2 g (94% yield).

1. customIn a 5-liter three-necked round-bottomed flask was placed
2. temperatureThe resulting mixture was refluxed for 3 hours
3. concentrationThe reaction mixture was concentrated
4. customa rotary evaporator
5. customThe crude reaction mixture
6. washThe resulting aqueous solution was washed once with 500 mL of ethyl acetate
7. temperaturecooled in an ice bath
8. customThe expected 4-amino-3-chloro-5-methoxyiminomethylbenzoic acid precipitated as a light yellow solid which
9. customwas separated by suction filtration
10. washThe filter cake was washed with a 1:2 mixture of ethyl ether and hexane yielding
11. customafter drying 185.2 g (94% yield)

ORD record

ord-860b8e50ccf8448c86273d6d4658289d

Source dataset

uspto-grants-1999_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05929098