[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[C:7]([CH:10]=[O:11])[CH:8]=2)[CH:3]=[N:2]1.[CH3:12][Mg]Br>C1COCC1>[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[C:7]([CH:10]([OH:11])[CH3:12])[CH:8]=2)[CH:3]=[N:2]1To a solution of 1H-indazole-6-carbaldehyde (200 mg, 1.37 mmol) in THF (7 mL) at −78° C. was added methyl magnesium bromide (1.4 mL, 4.11 mmol) dropwise under argon. The solution was warmed to rt and quenched with saturated ammonium chloride (2 mL). The mixture was extracted into ethyl acetate (3×10 mL), dried over MgSO4 and concentrated. The yellow oil was purified by silica gel chromatography (EtOAc/Hex 4:1) to yield the title compound as a clear oil (135 mg, 60%). 1H NMR (400 MHz, CDCl3) δ 8.07 (s, 1H), 7.76 (s, 1H), 7.50-7.47 (m, 2H), 5.05 (q, 1H, J=7.4 Hz), 1.57 (d, 3H, J=7.2 Hz); MS ESI [M+H]+, calcd for [C9H10N2O+H]+ 163.1; found m/z 163.0.
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