反应详情

温度

90 °C

1-Bromo-2-iodobenzene (0.32 mL, 2.4 mmol), copper(I) iodide (50 mg, 0.26 mmol) and bis(triphenylphosphine)palladium(II) chloride (88 mg, 0.12 mmol) were added to a degassed solution of 2-tributylstannylpyrazine (1.0 g, 2.4 mmol) in tetrahydrofuran (10 mL) and stirred at 90° C. under nitrogen for 22 hours. Diethyl ether was added to the cooled mixture, filtered through ‘Hyflo’ silica and concentrated in vacuo. Purification by flash column chromatography eluting with a 10-100% diethyl ether/isohexane gradient gave a pale yellow oil of 2-(2-iodophenyl)pyrazine (0.11 g, 16%) which contained some 2-(2-bromophenyl)pyrazine. 1H NMR (500 MHz, CDCl3) δ 8.85 (1H, d, J=1.4 Hz), 8.71-8.65 (1H, m), 8.59 (1H, d, J=2.5 Hz), 8.00 (1H, d, J=7.9 Hz), 7.49-7.46 (2H, m), 7.19-7.11 (1H, m); m/z (ES+) 283 [MH+].

1. filtrationfiltered through ‘Hyflo’ silica
2. concentrationconcentrated in vacuo
3. customPurification by flash column chromatography
4. washeluting with a 10-100% diethyl ether/isohexane gradient