反应详情

A solution of 4-[4-(t-butoxycarbonyl)piperazin-1-yl]-1H-indazole (5.00 g, 16.5 mmol) in N,N-dimethylformamide is treated with powdered potassium hydroxide (1.85 g, 33.07 mmol) and iodine (4.61 g, 18.2 mmol), stirred at room temperature for 16 h, diluted with ethyl acetate and quenched with 15% aqueous sodium metabisulfite. The phases are separated and the aqueous phase is extracted with ethyl acetate. The extracts and the organic phase are combined, washed with brine, dried over sodium sulfate and concentrated in vacuo to afford a crude solid. This solid is purified by column chromatography (silica gel, 10:90 to 15:85 to 20:80 ethyl acetate/hexanes) to afford the title product as a yellow solid, 2.40 g (35% yield) identified by HNMR and mass spectral analyses.

1. customquenched with 15% aqueous sodium metabisulfite
2. customThe phases are separated
3. extractionthe aqueous phase is extracted with ethyl acetate
4. washwashed with brine
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated in vacuo
7. customto afford a crude solid
8. customThis solid is purified by column chromatography (silica gel, 10:90 to 15:85 to 20:80 ethyl acetate/hexanes)