METHOD OF OBTAINING 4-{4-AMINO-2-CHLORO-5-[(5-CHLORO-2-METHYL-1H-BENZIMIDAZOL-6-YL)AMINO]PHENOXY}BENZOIC ACID Russian patent published in 2014 - IPC C07D235/14 

FIELD: chemistry.

SUBSTANCE: claimed invention relates to method of obtaining 4-{4-amino-2-chloro-5-[(5-chloro-2-methyl-1H- benzimidazol-6-yl)amino]phenoxy}benzoic acid, which includes acylation of 4,5-dichloro-2-nitroaniline with acetic anhydrite, nucleophilic substitution of chlorine atom, in interaction of two molecules of N-acetyl-4,5-dichloro-2-nitroaniline with each other and with 4-hydroxybenzoic acid in DMSO in presence of K₂CO₃, reduction of 4-{5-[(5-acetamido-2-chloro-4-nitrophenyl)amino]-2-chloro-4-nitrophenoxy}benzoic acid, with acylation of 4,5-dichloro-2-nitroaniline being carried out at temperature 90°C for 1 h and molar ratio of 4,5-dichloro-2-nitroaniline:acetic anhydrite = 1:2.0, nucleophilic substitution of chlorine atom is carried out in DMSO in presence of K₂CO₃ for 3 hours at temperature 110°C and molar ratio of N-acetyl-4,5-dichloro-2-nitroaniline:4-hydroxybenzoic acid = 2:1, reduction of 4-{5-[(5-acetamido-2-chloro-4-nitrophenyl)amino]-2-chloro-4-nitrophenoxy}benzoic acid is carried out with SnCl₂·2H₂O at temperature 110°C for 1 h in icy acetic acid and molar ratio 4-{5-[(5-acetamido-2-chloro-4-nitrophenyl)amino]-2-chloro-4-nitrophenoxy}benzoic acid: SnCl₂-2H₂O = 1:6.5.

EFFECT: highly effective method of obtaining 4-{4-amino-2-chloro-5-[(5-chloro-2-methyl-1H- benzimidazol-6-yl)amino]phenoxy}benzoic acid, characterized by small time consumption on obtaining target product with high output and high purity.

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