Boron tribromide → HCID 178524229, compound
Reaction equation
C[O:2][C:3]1[C:8]2=[CH:9][CH:10]=[C:11]3[C:20]([N:19]=[C:18]4[C:13]([CH:14]=[CH:15][CH:16]=[C:17]4[C:21]([OH:23])=[O:22])=[N:12]3)=[C:7]2[CH:6]=[CH:5][CH:4]=1.B(Br)(Br)Br>ClCCl>[OH:2][C:3]1[C:8]2=[CH:9][CH:10]=[C:11]3[C:20]([N:19]=[C:18]4[C:13]([CH:14]=[CH:15][CH:16]=[C:17]4[C:21]([OH:23])=[O:22])=[N:12]3)=[C:7]2[CH:6]=[CH:5][CH:4]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of 4-methoxy-benzo[a]phenazine-11-carboxylic acid (II.1, see Reference Example 1A) (441 mg) in dichloromethane (30 mL) cooled to 0° C. was added a 1.0M solution of boron tribromide in dichloromethane (7.25 mL). The reaction mixture was allowed to warm to room temperature and then stirred for 16 hours. The mixture was then poured onto ice/water yielding 4-hydroxy-benzo[a]phenazine-11-carboxylic acid as a red/brown solid which was collected by filtration and air dried (230 mg).