反应详情

[2-(1-Cyclohexenyl)-4-oxo-4H-[1]-benzopyran-8-yl]acetic acid (568 mg) and triethylamine (0.34 ml) were added to dichloromethane (6 ml) and to the mixture was added dropwise diphenylphosphoryl azide (0.52 ml) with stirring at room temperature. After stirring for 30 minutes, 30% aqueous methylamine solution (5 ml) was added and stirring was continued for additional 2 hours. The solvent was distilled off under reduced pressure and n-hexane was added to the residue. Crystals deposited were filtered. The crude crystals were recrystallized from methanol to obtain the title compound as prisms, yield 380 mg (64%), m.p. 213°-214° C.

1. stirringAfter stirring for 30 minutes
2. stirringstirring
3. distillationThe solvent was distilled off under reduced pressure and n-hexane
4. additionwas added to the residue
5. filtrationCrystals deposited were filtered
6. customThe crude crystals were recrystallized from methanol