反应详情

温度

105 °C

A mixture of 2,5-dibromopyridine (4.33 g, 17.7 mmol), 3-bromophenylboronic acid (4.70 g, 21.3 mmol), tetrakis(triphenylphosphine) palladium (0) (800 mg, 0.692 mmol), 2 M Na2CO3(aq) (18 cm3), EtOH (18 cm3) and toluene (50 cm3) was degassed and heated at reflux with a bath temperature of 105° C. under argon for 23 h. The reaction was allowed to cool and the two phases were separated. The aqueous layer was extracted with ether (3×15 cm3). The organic layer and the ether extracts were combined, washed with brine (1×40 cm3) and dried over anhydrous sodium sulfate. The solvents were completely removed to leave an orange oil. The oil was purified by column chromatography over silica gel using DCM-light petroleum (0:1 to 1:10) as eluent to give 2.50 g (45%) of B-1 as a pale yellow solid; δH(200 MHz; CDCl3) 7.26-7.42 (1 H, m, ArH), 7.57 (2 H, m, PyH & ArH), 7.88 (2 H, m, PyH & ArH), 8.14 (1 H, m, ArH), and 8.74 (1 H, m, PyH); m/z [CI(NH3)] 312, 314, 316 (MH+).

1. customwas degassed
2. temperatureheated
3. temperatureto cool
4. customthe two phases were separated
5. extractionThe aqueous layer was extracted with ether (3×15 cm3)
6. washwashed with brine (1×40 cm3)
7. dry with materialdried over anhydrous sodium sulfate
8. customThe solvents were completely removed
9. customto leave an orange oil
10. customThe oil was purified by column chromatography over silica gel
11. customto give 2.50 g (45%) of B-1 as a pale yellow solid