Ethyl Acetate → 3-Iodo-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-indazole-5-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

To a suspension of 3-iodo-1H-indazole-6-carbaldehyde (126.6 mg, 0.46 mmol) in CH2Cl2 (5 mL) and 50% aq. KOH (1.0 mL) was added tetrabutylammonium bromide (3.4 mg, 0.01 mmol) and the solution cooled to 0° C. (2-(Chloromethoxy)ethyl)trimethylsilane (0.10 mL, 0.56 mmol) was then added dropwise and the reaction stirred at 0° C. for 1.5 hours. The solution was then transferred to a sep. funnel containing ethyl acetate (200 mL) and the organic layer was washed with water (2×20 mL) and brine (20 mL), dried (Na2SO4) and the solvent removed in vacuo. The resulting residue was adsorbed onto silica using dichloromethane-methanol to dissolve, and evaporated to dryness. Chromatography (10 g silica SPE tube, Silicycle, 50-100% dichloromethane in hexane, 10% ethyl acetate in dichloromethane) to give 88 mg, 47%. 1H NMR: (400 MHz, CDCl3) δ 10.12 (s, 1H), 8.05 (m, 2H), 7.67 (d, J=9.2 Hz, 1H), 5.77 (s, 2H), 3.60 (m, 2H), 0.90 (m, 2H), −0.048 (s, 9H).

Provenance & Evidence