Sodium hydride → 5-Bromo-4-methoxy-1-(2-trimethylsilanyl-ethoxymethyl)-1H-indazole

Participants

Reaction Steps

To a stirred solution of 5-bromo-4-methoxy-1H-indazole (1.33 g, 5.9 mmol) in THF (20 mL) at 0° C., under a nitrogen atmosphere, was added sodium hydride (280 mg, 7 mmol) portionwise. After 5 min, (2-chloromethoxy-ethyl)-trimethylsilane (1.36 mL, 7.7 mmol) was added dropwise. After 3 hours, the reaction mixture was quenched with water (20 mL). The resulting biphasic mixture was separated, extracted with ethyl acetate (2×50 mL) and the combined organic layers were washed with brine (30 mL), dried (Na2SO4), filtered and concentrated in vacuo. The resulting residue was subjected to flash chromatography (SiO2, gradient 10-20% ethyl acetate in cyclohexane) to give the title compound as a yellow oil (1.19 g, 56%). LCMS (Method B): RT=4.91 min, [M+H]+=357.

Provenance & Evidence