Boron tribromide → 10-bromo-2-hydroxy-4H-pyrido[3,2,1-jk]carbazole-4-one
Reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[N:6]3[CH:19]=[CH:18][C:17](=[O:20])[C:8]4[CH:9]=[C:10]([O:15]C)[CH:11]=[C:12]([C:13]=2[CH:14]=1)[C:7]3=4.B(Br)(Br)Br>C(Cl)Cl>[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[N:6]3[CH:19]=[CH:18][C:17](=[O:20])[C:8]4[CH:9]=[C:10]([OH:15])[CH:11]=[C:12]([C:13]=2[CH:14]=1)[C:7]3=4Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
10-bromo-2-methoxy-4H-pyrido[3,2,1-jk]carbazole-4-one (3.2 g) obtained in Example 58 was suspended in anhydrous methylene chloride (500 ml), and boron tribromide (25 g) was added dropwise at room temperature. The mixture was stirred at room temperature for 12 hours and the reaction mixture was poured into ice water (1 L) and the crystals precipitated were recovered by filtration. The methylene chloride layer of the filtrate was washed with saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The two types of crystals thus obtained were combined, and the above-described procedure was repeated. The reaction mixture was poured into ice water (1 L), and the crystals precipitated were recovered by filtration. The crude crystals obtained were washed with a mixed solution of chloroform and methanol at an elevated temperature and recovered by filtration to obtain the title compound (2.4 g, 78%).
Workup
- customthe crystals precipitated
- filtrationwere recovered by filtration
- washThe methylene chloride layer of the filtrate was washed with saturated aqueous solution of sodium chloride
- dry with materialdried over anhydrous sodium sulfate
- customthe solvent was evaporated under reduced pressure
- customThe two types of crystals thus obtained
- customthe crystals precipitated
- filtrationwere recovered by filtration
- customThe crude crystals obtained
- washwere washed with a mixed solution of chloroform and methanol at an elevated temperature
- filtrationrecovered by filtration
Sources & evidence
- ORD record
- ord-df3f7bd262874c4880586c814416efaa
- Source dataset
- uspto-grants-2001_03
- Patent number
- US06197768B1
Reaction notes
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