反应详情

3-ethyl-1H-indazole-6-carboxylic acid (3.9 g, 0.020 mol), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (4.3 g, 0.022 mol) and 4-dimethylaminopyridine (3.11 g, 0.0254 mol), N,O-dimethylhydroxylamin hydrochloride (2.8 g, 0.028 mol) were dissolved in methylene chloride (200 mL) and N,N-dimethylformamide (20 mid) and the solution stirred at room temperature for one hour. The resulting mixture was poured in iced water. The aqueous layer was removed, and extracted with ethyl acetate (2×50 mL). The combined organics were washed with 1 N HCl, 2N NaOH, water, and brine, then dried. The solvent was removed in vacuo, and the residue was purified by column chromatography on silica gel eluting with a gradient of 50% ethyl acetate in hexanes to 100% ethyl acetate over 30 minutes to give 1.6 g (33%) of 3-ethyl-N-methoxy-N-methyl-1H-indazole-6-carboxamide.

1. customThe aqueous layer was removed
2. extractionextracted with ethyl acetate (2×50 mL)
3. washThe combined organics were washed with 1 N HCl, 2N NaOH, water, and brine
4. customdried
5. customThe solvent was removed in vacuo
6. customthe residue was purified by column chromatography on silica gel eluting with a gradient of 50% ethyl acetate in hexanes to 100% ethyl acetate over 30 minutes