[H-].[Na+].[C:3]1([OH:9])[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[Br:10][C:11]1[CH:20]=[CH:19][CH:18]=[C:17]2[C:12]=1[N:13]=[C:14](Cl)[C:15]([NH2:21])=[N:16]2>CN(C=O)C>[Br:10][C:11]1[CH:20]=[CH:19][CH:18]=[C:17]2[C:12]=1[N:13]=[C:14]([O:9][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1)[C:15]([NH2:21])=[N:16]2To a slurry of NaH (60% dispersion in mineral oil; 0.193 g, 4.84 mmol) in 5 mL DMF at 0° C. under N2 was added phenol (0.455 g, 4.84 mmol). Gas evolution was observed. The reaction was warmed to RT. After 5 min, 5-bromo-3-chloroquinoxalin-2-amine (0.250 g, 0.967 mmol) was added, and the reaction was sealed and stirred overnight. The reaction was partitioned between saturated aq. NH4Cl and EtOAc. The organic layer was sequentially washed with water (1×), and saturated aq. NaCl (1×), and then dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The material was treated with DCM and adsorbed onto 2 g silica gel and dried. The material was purified by silica gel chromatography using 0-60% EtOAc/hexane. The product-containing fractions were concentrated to afford 5-bromo-3-phenoxyquinoxalin-2-amine (0.209 g, 0.661 mmol, 68% yield) as a yellow solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 7.55 (1H, dt, J=7.6, 0.7 Hz), 7.37-7.51 (7H, m), 7.26-7.35 (2H, m). m/z (ESI, +ve) 316.0 (M+H)+.
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