反应详情

A well stirred mixture of methyl 2,6-dichloro-4-(methylcarbamoyl)benzoate (280 mg, 1 mmol, Step a) and anhydrous lithium iodide (429 mg, 3.2 mmol) in pyridine (3 mL) was heated under reflux for 3 hours. The reaction mixture was concentrated under vacuum to remove pyridine. The residue was acidified using ice-cooled dilute hydrochloric acid solution and partitioned with ethyl acetate. The combined organic layer was washed with brine, dried over sodium sulfate, and concentrated under vacuum to obtain a solid that upon triturating with cold diethyl ether yielded pure 2,6-dichloro-4-(methylcarbamoyl)benzoic acid (200 mg, 75%).

1. temperaturewas heated
2. temperatureunder reflux for 3 hours
3. concentrationThe reaction mixture was concentrated under vacuum
4. customto remove pyridine
5. temperaturecooled dilute hydrochloric acid solution
6. custompartitioned with ethyl acetate
7. washThe combined organic layer was washed with brine
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated under vacuum
10. customto obtain a solid that
11. customupon triturating with cold diethyl ether yielded pure 2,6-dichloro-4-(methylcarbamoyl)benzoic acid (200 mg, 75%)