Methyl iodide → 3-Iodo-1-methyl-1H-indazole

関与物質

反応条件

反応手順

In a 50 ml round-bottomed flask, 3-iodo-1H-indazole (1.0 g, 3.9 mmol) was dissolved in THF (12 ml) and the solution was cooled to 0° C. Potassium tert-butoxide (612 mg, 5.45 mmol) was added and the reaction mixture was stirred at 0° C. for 1.25 h. Methyl iodide (0.29 ml, 4.64 mmol) was added dropwise then the ice bath was removed and the reaction mixture was stirred at room temperature for 2 h. The reaction mixture was quenched with water and extracted with EtOAc (2×). The combined organic layers were washed with water and brine then dried over sodium sulfate, filtered and concentrated. The residue was purified by chromatography over silica gel with EtOAc/Hexanes (gradient 0-10% EtOAc) to afford 863 mg (86%) of 3-iodo-1-methyl-1H-indazole as a yellow oil. 1H NMR (CDCl3, 300 MHz): δ (ppm) 7.42-7.53 (m, 2H), 7.33-7.40 (m, 1H), 7.22 (ddd, J=8.0, 6.9, 0.9 Hz, 1H), 4.11 (s, 3H).

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