Sodium borohydride → HCID 71061027, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of the crude methyl 3-bromo-5-oxo-6,7,8,9-tetrahydro-5H-benzo[7]annulene-6-carboxylate from step A2 (350 mg, 1.18 mmol) in MeOH (5 mL) was slowly added NaBH4 (44.6 mg, 1.18 mmol) at 0° C. The mixture was stirred at 0° C. for 30 min. The solvent was removed in vacuo at rt. EtOAc (100 mL) was added and the organic layer was washed with water. The organic layer was concentrated, and the residue was purified using silica gel column chromatography (hexanes-60% EtOAc) to give methyl 3-bromo-5-hydroxy-6,7,8,9-tetrahydro-5H-benzo[7]annulene-6-carboxylate (230 mg, 0.769 mmol, 65% yield). 1H NMR (500 MHz, chloroform-d) δ 7.81-7.39 (m, 1H), 7.35-7.23 (m, 1H), 7.01-6.87 (m, 1H), 5.13-4.96 (m, 1H), 3.77-3.65 (m, 3H), 3.39-3.22 (m, 1H), 3.20-2.56 (m, 3H), 2.47-1.86 (m, 3H), 1.65-1.30 (m, 1H).

Provenance & Evidence