反应详情

In methanol (30 ml) was dissolved methyl (4-amino-2-fluoro-3-hydroxyphenyl)acetate (1.0 g, 5.02 mmol). To the resulting solution was added 4-fluoro-2-methylphenyl isothiocyanate (0.74 ml, 5.23 mmol). After the mixture was stirred at room temperature for 5 days, mercuric oxide (yellow) (1.14 g, 4.36 mmol) was added thereto. The mixture was stirred at 70° C. for 6 hours. After cooling to room temperature, the reaction mixture was filtered through Celite and washed with methanol. The filtrate was distilled under reduced pressure to remove the solvent. The residue was purified by chromatography on a silica gel column, whereby from chloroform/ethyl acetate (30/1) eluate fractions, methyl (2-(4-fluoro-2-methylphenylamino)-7-fluoro-6-benzoxazolyl)acetate (1.32 g, 91%) was obtained as a colorless solid.

1. stirringThe mixture was stirred at 70° C. for 6 hours
2. temperatureAfter cooling to room temperature
3. filtrationthe reaction mixture was filtered through Celite
4. washwashed with methanol
5. distillationThe filtrate was distilled under reduced pressure
6. customto remove the solvent
7. customThe residue was purified by chromatography on a silica gel column, whereby from chloroform/ethyl acetate (30/1) eluate fractions