Sodium Carbonate → 3-Bromo-5-(thien-3-yl)benzonitrile

참여 물질

반응 단계

A mixture of 3,5-dibromobenzonitrile (3 g, 11.5 mmol), thiophene-3-boronic acid (2.35 g, 18 mmol), dichlorobis(triphenylphosphine)palladium(II)(1.21 g, 1.7 mmol), tri-o-tolylphosphine (0.524 g, 1.7 mmol), sodium carbonate (3.46 g, 33 mmol) in aqueous acetonitrile (1:10), 110 mL) was refluxed under nitrogen for 6 hours, cooled to room temperature, concentrated under reduced pressure, suspended in hydrochloric acid (2N, 50 mL), and extracted with diethyl ether (3×80 mL). The combined organic extracts were washed with water (150 mL), saturated aqueous sodium bicarbonate (150 mL), and brine (50 mL), dried over magnesium sulfate, adsorbed onto silica, chromatographed on silica and eluted with a mobile phase of ethyl acetate in hexane. The first fraction was concentrated under reduced pressure to leave 3-bromo-5-(thien-3-yl)benzonitrile in the form of a yellow amorphous solid. Yield 1.47 g (48 percent). mp 62-63° C.; 1H NMR (CDCl3) δ 7.94 (t, J=1.8 Hz, 1H), 7.79 (t, J=1.5 Hz, 1H), 7.69 (t, J=1.8 Hz, 1H), 7.54 (dd, J1=3.0 Hz, J2=1.5 Hz, 1H), 7.46 (dd, J1=5.1 Hz, J2=3.0 Hz, 1H), 7.34(dd, J1=4.8 Hz, J2=1.5 Hz, 1H); EI/MS 265 m/e (M+); IR (KBr) σ cm−1 2230.

출처 및 근거