N-bromobutanimide → 7-Bromo-1-[2-(tert-butyldimethyl-silanyloxy)-propyl]-1H-indazol-6-ol

Participants

Reaction Steps

To a solution of the product from Step B (6.00 g, 19.6 mmol) in anhydrous THF (300 mL) at 0° C. was added N-bromosuccinimide (3.49 g, 19.6 mmol) in 10 portions over 20 min. The mixture was poured into a saturated aqueous solution of sodium bisulfite (300 mL) and extracted with EtOAc (3×100 mL). The combined extracts were dried (MgSO4) and evaporated to a residue (6.39 g). Chromatography (silica, 10% EtOAc/hexane) gave a solid (4.95 g, 66%): LC/MS (+APCI) m/z 385, 387 (M+H).

Provenance & Evidence