反应详情

A solution of 1 g of 2-(3,4-diethoxyphenyl)-4-(3-carboxy-4-hydroxyphenyl)thiazole in 5 ml of acetic anhydride was stirred at 100° C. for 4 hours with heating. The solvent was distilled off. The residue was dissolved in 50 ml of ethyl acetate. To the solution was added 10 ml of a saturated sodium hydrogencarbonate solution, and phase separation was conducted. The ethyl acetate layer was made acidic with 10% hydrochloric acid, washed with 10 ml of a saturated aqueous sodium chloride solution, dried and subjected to distillation to remove the solvent. The residue was recrystallized from ethyl acetate to obtain 145 mg of 2-(3,4-diethoxyphenyl)-4-(3-carboxy-4-acetyloxyphenyl)thiazole.

1. temperaturewith heating
2. distillationThe solvent was distilled off
3. dissolutionThe residue was dissolved in 50 ml of ethyl acetate
4. additionTo the solution was added
5. custom10 ml of a saturated sodium hydrogencarbonate solution, and phase separation
6. washwashed with 10 ml of a saturated aqueous sodium chloride solution
7. customdried
8. distillationsubjected to distillation
9. customto remove the solvent
10. customThe residue was recrystallized from ethyl acetate