Sodium Carbonate → HCID 21716778, compound

Participants

Reaction Steps

A deoxygenated solution of 3-bromo-5-thiophen-3-yl-pyridine (2.50 g, 10.4 mmol, 1 equiv), 1-(t-butyloxycarbonyl)-3-indoleboronic acid (4.073 g, 15.6 mmol, 1.50 equiv), Pd(PPh3)4 (601 mg, 0.520 mmol, 0.0500 equiv), and 2.0 M Na2CO3 (10.4 mL, 20.8 mmol, 2.00 equiv) in dioxane (120 ml) was heated under argon at reflux for 20 h. The reaction mixture was allowed to cool, then partitioned between water (500 mL) and ethyl acetate (3×150 mL). The combined organic layers were washed sequentially with water (500 mL) and brine (500 ml), then dried over sodium sulfate and concentrated. The residue was purified by flash column chromatography (40% ethyl acetate in hexane) to afford 3-(5-thiophen-3-yl-pyridin-3-yl)-1-(t-butyloxycarbonyl)-indole as a colorless oil. The oil was dissolved in ethyl acetate (100 ml), and the resulting solution was cooled to 0° C., then saturated with HCl gas. The solution was allowed to warm to 23° C. and stirred for 30 minutes. The precipitate was filtered and washed with ethyl ether (50 mL). The solid was then partitioned between ethyl acetate (150 mL) and aqueous saturated NaHCO3 solution (150 mL). The organic layer was dried over Na2SO4 and concentrated to give compound 1 (3-(5-thiophen-3-yl-pyridin-3-yl)-indole) as a white solid.

Provenance & Evidence