Carbon tetrabromide → 5-(Bromomethyl)-7-methyl-2-((2-(trimethylsilyl)ethoxy)methyl)-2H-indazole

Participants

Reaction Steps

To a solution of (7-methyl-2-((2-(trimethylsilyl)ethoxy)methyl)-2H-indazol-5-yl)methanol (138 mg, 0.472 mmol) and carbon tetrabromide (235 mg, 0.708 mmol) in tetrahydrofuran (1 mL) at 0° C. was added triphenylphosphine (186 mg, 0.708 mmol). The resulting solution was stirred at room temperature for 30 min. The reaction was diluted with several volumes of pentane and filtered to remove undissolved solids. The organics were concentrated and purified by column chromatography (5→12% EtOAc/Hex) to give 114 mg (68%) as a colorless oil. 1H-NMR (CDCl3, 500 MHz) δ 8.03 (s, 1H), 7.48 (s, 1H), 7.06 (s, 1H), 5.68 (s, 2H), 4.55 (s, 2H), 3.61 (m, 2H), 2.59 (s, 3H), 0.91 (m, 2H), −0.05 (s, 9H); 13C NMR (126 MHz, CDCl3) δ ppm 148.8, 131.6, 129.0, 126.6, 123.3, 121.6, 118.1, 81.7, 67.3, 35.4, 17.7, 17.1, −1.5.

Provenance & Evidence