反应详情

(1-Methyl-1H-pyrazol-5-yl)boronic acid (C1) (1.00 g, 7.94 mmol), 2-bromo-5-(trifluoromethyl)pyridine (1.79 g, 7.92 mmol), dichlorobis(triphenylphosphine)palladium(II) (279 mg, 0.397 mmol), and sodium carbonate (3.37 g, 31.8 mmol) were combined in 1,2-dimethoxyethane (30 mL) and water (3 mL), and the reaction mixture was heated at reflux for 18 hours. After the reaction had cooled to room temperature, it was concentrated in vacuo, diluted with additional water, and extracted with ethyl acetate (2×300 mL). The combined organic layers were washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated under reduced pressure. Purification via silica gel chromatography (Gradient: 0% to 100% ethyl acetate in heptane) provided the product. Yield: 630 mg, 2.77 mmol, 35%. 1H NMR (400 MHz, CD3OD) δ 3.95 (s, 3H), 6.60 (d, J=2.2 Hz, 1H), 7.58 (d, J=2.0 Hz, 1H), 7.94 (br d, J=8.2 Hz, 1H), 8.19-8.23 (m, 1H), 8.89 (br d, J=2 Hz, 1H).

1. temperatureat reflux for 18 hours
2. concentrationit was concentrated in vacuo
3. additiondiluted with additional water
4. extractionextracted with ethyl acetate (2×300 mL)
5. washThe combined organic layers were washed with saturated aqueous sodium chloride solution
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customPurification via silica gel chromatography (Gradient: 0% to 100% ethyl acetate in heptane)
10. customprovided the product