Ethyl vinyl ether → 7-Bromo-6-[3-bromo-2-(1-ethoxyethoxy)-propoxy]-1-[(S)-2-(tert-butyldimethyl-silanyloxy)-propyl]-1H-indazole

Participants

Reaction Steps

To a solution of the product from Step E (1.85 g, 3.54 mmol) and p-toluenesulfonic acid (0.01 g) in dichloromethane (50 mL) at 0° C. was added ethyl vinyl ether (1 mL, 10.5 mmol). After 30 min the reaction was quenched with a saturated solution of sodium bicarbonate (50 mL) and extracted with EtOAc (3×80 mL). Evaporation and purification by chromatography (silica, 1% to 8% EtOAc/hexane) gave a viscous oil (1.79 g, 81%): LC/MS (+APCI) m/z 595 (M+H).

Provenance & Evidence