Boron tribromide → 5,7-dihydroxy-3-(4-hydroxyphenyl)-4(3H)-quinazolinone
Reaktionsgleichung
C[O:2][C:3]1[CH:12]=[C:11]([O:13]C)[CH:10]=[C:9]2[C:4]=1[C:5](=[O:23])[N:6]([C:15]1[CH:20]=[CH:19][C:18]([O:21]C)=[CH:17][CH:16]=1)[CH:7]=[N:8]2.B(Br)(Br)Br>C(Cl)Cl>[OH:2][C:3]1[CH:12]=[C:11]([OH:13])[CH:10]=[C:9]2[C:4]=1[C:5](=[O:23])[N:6]([C:15]1[CH:16]=[CH:17][C:18]([OH:21])=[CH:19][CH:20]=1)[CH:7]=[N:8]2Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
To an ice-cooled mixture of 365 mg (1.17 mmol) of 5,7-dimethoxy-3-(4-methoxyphenyl)-4(3H)-quinazolinone, prepared according to the procedures described in Example 18 or 19, and 10 ml of CH2Cl2, 3 ml of BBr3 (31.7 mmol) was added. The mixture was stirred at room temperature for 2 days. The solvent was evaporated, the obtained residue treated with a cold NaHCO3 solution and extracted with EtOAc. The organic layer was washed with water and brine, dried over MgSO4 and evaporated to yield a solid which purification by flash chromatography on silica gel (loaded with CH2Cl2 and eluted with 66% EtOAc in hexane) gave 165 mg of 5,7-dihydroxy-3-(4-hydroxyphenyl)-4(3H)-quinazolinone (40% yield) as a white solid.