Boron tribromide → 1-[5-Hydroxy-2-(4-pyridinylamino)benzoyl]piperidine
Reaction equation
C[O:2][C:3]1[CH:4]=[CH:5][C:6]([NH:17][C:18]2[CH:23]=[CH:22][N:21]=[CH:20][CH:19]=2)=[C:7]([CH:16]=1)[C:8]([N:10]1[CH2:15][CH2:14][CH2:13][CH2:12][CH2:11]1)=[O:9].B(Br)(Br)Br>C(Cl)Cl>[OH:2][C:3]1[CH:4]=[CH:5][C:6]([NH:17][C:18]2[CH:23]=[CH:22][N:21]=[CH:20][CH:19]=2)=[C:7]([CH:16]=1)[C:8]([N:10]1[CH2:11][CH2:12][CH2:13][CH2:14][CH2:15]1)=[O:9]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
1-[5-Methoxy-2-(4-pyridinylamino)benzoyl]piperidine (Example 30b) (9.2 g) was dissolved in 100 ml of methylene dichloride. To this solution was added dropwise 80 ml of boron tribromide solution (0.8M in methylene dichloride). The mixture was kept at room temperature overnight and the solvent removed at reduced pressure. The residue was made basic with aqueous potassium carbonate and the solid product collected by filtration. The product was dissolved in methanol and acetonitrile added to produce 4.9 g of 1-[5-hydroxy-2-(4-pyridinylamino)benzoyl]piperidine. A further recrystallization from methanol gave a sample with m.p. 242°-243° C.(decompn.).