Boron tribromide → HCID 44610276, Verbindung
Reaktionsgleichung
[Br:1][C:2]1[CH:3]=[C:4]([C:11]([N:13]2[CH2:18][CH2:17][O:16][C:15]3[CH:19]=[N:20][CH:21]=[CH:22][C:14]2=3)=[O:12])[CH:5]=[C:6]([Br:10])[C:7]=1[O:8]C.B(Br)(Br)Br.C(=O)([O-])O.[Na+]>>[Br:1][C:2]1[CH:3]=[C:4]([C:11]([N:13]2[CH2:18][CH2:17][O:16][C:15]3[CH:19]=[N:20][CH:21]=[CH:22][C:14]2=3)=[O:12])[CH:5]=[C:6]([Br:10])[C:7]=1[OH:8]Komponenten
4
Versuchsvorschrift
By the same method as in Example 3, (3,5-dibromo-4-methoxy-phenyl)-(2,3-dihydro-pyrido[3,4-b][1,4]oxazin-1-yl)-methanone (60 mg, 0.140 mmol) and 1M solution of boron tribromide (0.84 ml, 0.840 mmol) were reacted, and then the reaction mixture was neutralized (pH=7) by using saturated solution of sodium hydrogen carbonate and extracted with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulfate (Na2SO4), filtered and evaporated under reduced pressure to obtain solid. The obtained solid was recrystallized from dichloromethane and n-hexane to obtain the target compound 6, (3,5-dibromo-4-hydroxy-phenyl)-(2,3-dihydro-pyrido[3,4-b][1,4]oxazin-1-yl)-methanone, as white solid (28 mg, 48%).