[CH3:1][C:2]1[N:7]=[C:6]2[CH:8]=[CH:9][O:10][C:5]2=[CH:4][CH:3]=1.CC(N=NC(C#N)(C)C)(C#N)C.C1C(=O)N([Br:30])C(=O)C1>>[Br:30][CH2:1][C:2]1[N:7]=[C:6]2[CH:8]=[CH:9][O:10][C:5]2=[CH:4][CH:3]=1To a solution of 1.46 g (11.0 mmol) of 5-methylfuro[3,2b]pyridine (from Step 2) and 100 mg AIBN in 35 mL of CC14 was added 2.1 g (11.6 mmol) of NBS. The mixture was stirred at 75° C. under radiation from a 150 W spot light for 1 hr. Another portion of NBS was added (1.0 g) and the reaction was allowed to proceed for another 1.5 hr. The reaction was allowed to cool to r.t., diluted with aqueous NH4OAc 25% w/v (150 mL) and the mixture was extracted with EtOAc. The organic layer was dried over MgSO4 and concentrated. The resulting residue was purified by chromatography on silica gel eluted with 20-25 % EtOAc in hexane to give the title compound as a colorless oil.
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