反应详情

3-Methyl-6-nitro-1H-indazole (436 mg, 2.46 mmol) was dissolved in 25 ml of dichloromethane at room temperature. DMAP (5 mg) and pyridine (1.1 eq, 0.38 ml) were added followed by tosyl chloride (1.1 eq, 516 mg). The mixture was allowed to stir at room temperature overnight. The mixture was filtered and the filtrate was concentrated in vacuo. The residue was purified by flash chromatography (gradient 9:1 to 4:1 Hexanes/Ethyl Acetate) to give 3-methyl-6-nitro-1-(toluene-4-sulfonyl)-1H-indazole (850 mg, quant) as a light brown crystalline solid.

1. filtrationThe mixture was filtered
2. concentrationthe filtrate was concentrated in vacuo
3. customThe residue was purified by flash chromatography (gradient 9:1 to 4:1 Hexanes/Ethyl Acetate)