Ethyl Acetate → tert-Butyl 2-bromo-3-cyclohexyl-1H-indole-6-carboxylate

Participants

Reaction Steps

To a solution (0.14 M) of tert-butyl-3-cyclohexyl-1H-indole-6-carboxylate in CCl4 was added NBS (1.1 eq.) portionwise over a period of 1 h at RT. The resulting mixture was stirred 2 h at RT, then a saturated aqueous solution of sodium thiosulfate was added and the reaction mixture vigorously stirred for 1 h. EtOAc was then added and the organic layer was separated and washed with a saturated aqueous solution of sodium thiosulfate (3×) then dried over Na2SO4 and evaporated. The residue was purified by silica gel chromatography (Flashmaster Personal, petroleum ether:EtOAc, 20:1) to give the title compound (68%) as a solid. 1H NMR (300 MHz, DMSO-d6, 300 K) δ 1.33-1.39 (m, 3H), 1.54 (s, 9H), 1.65-1.99 (m, 7H), 2.73-2.81 (m, 1H), 7.52 (d, J 7.6, 1H), 7.70 (d, J 77.6, 1H), 7.83 (s, 1H), 11.92 (br s, 1H); MS (ES+) m/z 379 (M+H)+.

Provenance & Evidence