[OH-].[K+].[CH3:3][C:4]1[C:12]2[C:7](=[CH:8][CH:9]=[C:10]([CH:13]=O)[CH:11]=2)[NH:6][N:5]=1.[C:15]([C:18]1[CH:23]=[CH:22][C:21]([NH:24]C(=O)C)=[CH:20][C:19]=1[CH3:28])(=[O:17])[CH3:16].Cl.C([O-])(O)=O.[Na+]>C(O)C>[NH2:24][C:21]1[CH:22]=[CH:23][C:18]([C:15](=[O:17])/[CH:16]=[CH:13]/[C:10]2[CH:11]=[C:12]3[C:7](=[CH:8][CH:9]=2)[NH:6][N:5]=[C:4]3[CH3:3])=[C:19]([CH3:28])[CH:20]=1To a solution of KOH (1.5 g, 26 mmol) in 20 mL ethanol were added 3-methyl-1H-indazole-5-carbaldehyde (see Note 1 for synthesis) (0.850 g, 5.3 mmol) and commercially available N-(4-acetyl-3-methylphenyl)acetamide (1.0 g, 5.3 mmol). The reaction mixture was heated to 80° C. for 24 hours and then cooled down to room temperature. After acidification with 1N HCl, the mixture was brought to pH 8 with saturated aqueous NaHCO3 and extracted twice with ethyl acetate (2×100 mL). The combined organic phases were washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo. The product was purified by SiO2 flash chromatography (60:40 to 50:50 hexanes/ethyl acetate) to afford (E)-1-(4-amino-2-methylphenyl)-3-(3-methyl-1H-indazol-5-yl)prop-2-en-1-one (0.500 g, 32%). 1H NMR (400 MHz, d6-DMSO): δ 12.8 (s, 1H), 8.12 (s, 1H), 7.81 (dd, 1H), 7.78 (d, 1H), 7.61 (d, 2H), 7.48 (d, 1H), 6.45 (m, 2H), 5.88 (br s, 1H), 3.06 (s, 3H), 2.42 (s, 3H); MS (EI) for C18H17N3O: 292.3 (MH+).
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