O[C:2]1[N:3]=[CH:4][C:5]([O:11][CH3:12])=[C:6]2[C:10]=1[NH:9][CH:8]=[CH:7]2.C1(OC)C=CC=CC=1.P(Br)(Br)([Br:23])=O>>[Br:23][C:2]1[N:3]=[CH:4][C:5]([O:11][CH3:12])=[C:6]2[C:10]=1[NH:9][CH:8]=[CH:7]2To a flask containing 7-hydroxy-4-methoxy-6-azaindole (0.200 g, 1.22 mmol) was added anisole (3 mL) and then POBr3 (1.57 g, 6.09 mmol). The system was purged with Ar and then it was heated at 160° C. (oil bath temperature) for 1 h. The reaction mixture was then allowed to cool to room temperature, quenched with 2M HBr (5 mL) and extracted with methyl t-butyl ether. The aqueous phase was separated and the pH was adjusted to 6-7, after which it was extracted with EtOAc. The resulting organic phase was dried (MgSO4) and evaporated to give a solid residue which was chromatographed (SiO2/5% MeOH-DCM) to afford the title compound (0.076 g, 27%) as a white solid:
불러오는 중…