Ethyl Acetate → methyl 6-chloro-5-(2-fluoro-4-methoxyphenyl)-1H-indole-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 5-bromo-6-chloro-1H-indole-3-carboxylate (150 mg, 0.52 mmol), (3-fluoro-4-methoxyphenyl)boronic acid (93 mg, 0.55 mmol) and aqueous 2M potassium carbonate (2M, 1.04 mL, 2.08 mmol) in toluene (3.0 mL) and ethanol (1.0 mL) was degassed with nitrogen for 10 minutes then treated with [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (20.0 mg, 0.026 mmol). The reaction mixture was then heated at 110° C. for 2 h in a sealed reaction vessel, which caused the reaction mixture to appear burnt orange. The cooled reaction mixture was poured into ethyl acetate and water. The layers were separated and the aqueous layer was back-extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The material was then dissolved in ethyl acetate and methanol then silica gel was added. The solvent was removed and the crude material adsorbed onto silica gel was added to a column of silica gel and eluted with ethyl acetate/heptane (1:4 to 1:1) to provide the desired product (55 mg, 32% yield) as a tan solid. MS (ES+) 334.5 (M+H)+. 1H NMR (400 MHz, DMSO-d6) δ 12.07 (br. s., 1H), 8.15 (s, 1H), 7.86 (s, 1H), 7.63 (s, 1H), 7.26 (t, J=8.69 Hz, 1H), 6.90 (dd, J=11.91, 2.15 Hz, 1H), 6.85 (dd, J=8.49, 2.24 Hz, 1H), 3.80 (s, 3H), 3.76 (s, 3H).

Provenance & Evidence