Br[C:2]1[C:7]([Br:8])=[CH:6][C:5]([O:9][CH3:10])=[C:4]([O:11][CH3:12])[N:3]=1.C[C:14]([N:16](C)C)=O>[C-]#N.[C-]#N.[Zn+2].[Zn].C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.[Pd].[Pd].C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.[Fe+2]>[Br:8][C:7]1[C:2]([C:14]#[N:16])=[N:3][C:4]([O:11][CH3:12])=[C:5]([O:9][CH3:10])[CH:6]=1To a mixture of 2,3-dibromo-5,6-dimethoxypyridine (150 mg, 0.505 mmol), Zn(CN)2 (30 mg, 0.253 mmol), Zn powder (33 mg, 0.051 mmol), Pd2(dba)3 (13.9 mg, 0.015 mmol) and DPPF (8.4 mg, 0.015 mmol), under argon, was added DMA (1.5 mL) and stirred at 120° C. for 3.5 h. Cooled to room temperature, filtered and purified by preparative HPLC (10-95% CH3CN/H2O over 20 min, 0.05% added TFA). The desired fractions were loaded onto a Strata-X-C cation exchange column. After washing the column with water and MeOH, the column was eluted with 5% NH4OH in MeOH to give 32 mg (26%) of 3-bromo-5,6-dimethoxypyridine-2-carbonitrile as a tan solid. LC/MS (M+H)+ 243.1.
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