Methyl iodide → Tert-butyl 2-bromo-4,5-dimethyl-5,6,7,8,9,10-hexahydro-7,10-epiminocyclohepta[b]indole-carboxylate

Participants

Reaction Steps

To a solution of the product of step B (410 mg, 1.05 mmol) in DMF (3.5 ml) at 0° C., under nitrogen was added sodium hydride (60% dispersion in mineral oil, 51 mg, 2.09 mmol). The mixture was stirred for 45 min at 0-5° C. before iodomethane (0.13 mL, 2.09 mmol) was added. The mixture was stirred for a further 90 min then quenched with ice water. The mixture was diluted with ethyl acetate, washed with water, brine and dried over anhydrous sodium sulfate. Concentration in vacuo afforded a viscous oil which was dissolved in a minimal amount of ethyl acetate and precipitated by addition of hexanes. The separated solid was filtered and dried in vacuo to give tert-butyl 2-bromo-4,5-dimethyl-5,6,7,8,9,10-hexahydro-7,10-epiminocyclohepta[b]indole-carboxylate (340 mg, 80%) as an off-white solid. 1H NMR (CDCl3, 300 MHz): δ 7.43 (d, J=1.2 Hz, 1H), 6.94 (d, J=1.2 Hz, 1H), 5.05-5.30 (m, 1H), 4.52-4.70 (m, 1H), 3.80 (s, 3H), 3.15-3.47 (m, 1H), 2.69 (s, 3H), 2.43 (dd, J=15.9, 0.9 Hz, 1H), 2.23-2.30 (m, 1H), 2.08-2.22 (m, 1H), 1.85-1.95 (m, 1H), 1.58-1.64 (m, 1H), 1.39 (br s, 9H).

Provenance & Evidence