摘要 |
Disclosed is a method of making 3-methoxy-2,4,5-trifluorobenzoic acid. A tetrafluorophthalimide is reacted with an alkali metal hydroxide to produce a mixture of alkali metal salts of 4-hydroxy-3,5,6-trifluoro-N-alkylphthalamic acid and 3-hydroxy-2,4,5-trifluoro-N-alkylbenzamide. Those products are reacted with a methylating agent to produce 4-methoxy-3,5,6-trifluoro-N-alkylphthalamic acid and 3-methoxy-2,4,5-trifluoro-N-alkylbenzamide. Those products are reacted with an acid to produce 4-methoxy-3,5,6-trifluorophthalic acid and 3-methoxy-2,4,5-trifluorobenzoic acid. Finally, the 4-methoxy-3,5,6-trifluorophthalic acid is reacted with a decarboxylating agent to produce additional 3-methoxy-2,4,5-trifluorobenzoic acid.
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