反应详情

20 g (104.9 mmol) of 2-naphthyl chloride and 2.5 g (15.5 mmol) of 4-aminoresorcinol hydrochloride were introduced into a three-necked flask provided with a thermometer and a cooling condenser, and the mixture was heated at 135° to 205° C. for 1 hour, then excessive acid chloride was removed by distillation. To the residue, 8.3 g (207.5 mmol) of NaOH, 60 ml of THF, 60 ml of water and 30 ml of methanol were added, and the mixture was stirred at room temperature for about 2 hours. The reaction solution was extracted with ethyl acetate, the extract was washed with saturated sodium chloride water solution, and ethyl acetate was distilled off. Recrystallizing the residue with water/methanol/THF and drying the crystal, there was obtained 1.92 mg (7.36 mmol) of 2-(2-naphthyl)-6-hydroxybenzoxazole. The yield was 47.5%.

1. customprovided with a thermometer and a cooling condenser
2. temperaturethe mixture was heated at 135° to 205° C. for 1 hour
3. customexcessive acid chloride was removed by distillation
4. extractionThe reaction solution was extracted with ethyl acetate
5. washthe extract was washed with saturated sodium chloride water solution, and ethyl acetate
6. distillationwas distilled off
7. customRecrystallizing the residue with water/methanol/THF
8. customdrying the crystal