[CH3:1][O:2][C:3]1[CH:4]=[N:5][C:6]2[CH:7]=[CH:8][CH:9]=[C:10]([CH:13]=[O:14])[C:11]=2[N:12]=1.[BH4-].[Na+]>CCO>[CH3:1][O:2][C:3]1[CH:4]=[N:5][C:6]2[C:11]([N:12]=1)=[C:10]([CH2:13][OH:14])[CH:9]=[CH:8][CH:7]=2To a stirred suspension of 3-methoxy-quinoxaline-5-carbaldehyde (4.05 g, 21.5 mmol; see WO 2006/032466) in EtOH (150 mL) cooled at 0° C., NaBH4 (814 mg, 21.5 mmol) was added in one portion. The reaction mixture was warmed to rt and stirred for 1 h. The mixture was quenched at 0° C. by addition of 1M HCl until H2 evolvement ceased, then concentrated under reduced pressure. The phases were separated between EA and sat. aq. NaHCO3, the org. layer was dried over MgSO4 and concentrated under reduced pressure. The residue was chromatographed on SiO2 (DCM-MeOH—NH4OH: 1000:50:4) to afford the title alcohol as a dark yellow solid (2.92 g, 71% yield).
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