N-bromobutanimide → tert-Butyl 2-bromo-3-cyclohexyl-1H-indole-6-carboxylate

Participants

Reaction Steps

N-bromosuccinimide (1.1 eq) was added portionwise over 1 h to tert-butyl 3-cyclohexyl-1H-indole-6-carboxylate in CCl4 (from Step 4, 0.07 M) with vigorous stirring. The reaction was stirred at RT for a further hour following complete addition of NBS. The CCl4 was then removed in vacuo and the residue taken up in EtOAc. The organics were washed with a saturated aqueous solution of sodium thiosulfate (twice), brine, dried over Na2SO4, filtered and concentrated in vacuo. Purification was by flash chromatography (5-20% EtOAc/PE gradient) to yield the title compound (57%); MS (ES+) m/z 380 (M+H)+, 378 (M+H)+.

Provenance & Evidence