| 摘要 |
4,5-Difluoroanthranilic acid may be prepared by decarboxylating 4,5-difluorophthalic anhydride or 4,5-difluorophthalic acid by heating in dimethyl acetamide, N-methyl-2-pyrrolidone or quinoline, optionally by reaction with copper, copper oxide, copper salts, or halides and salts of Zn, Cd, Ag and Ni as a catalyst, whereby 3,4-difluorobenzoic acid is formed; nitrating said 3,4-difluorobenzoic acid in a mixture of nitric and sulfuric acids to form 2-nitro-4,5-difluorobenzoic acid, and reducing said 2-nitro-4,5-difluorobenzoic acid to form 4,5-difluoroanthranilic acid.
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