反应详情

To a solution of 2-bromo-3-chloropyridine (Matrix, 1.651 g, 8.58 mmol), 4,4,6-trimethyl-2-(3,3,3-trifluoroprop-1-en-2-yl)-1,3,2-dioxaborinane (Frontier, 2.0 g, 9.01 mmol), and potassium carbonate (4.74 g, 34.3 mmol) in degassed 1,2-dimethoxyethane (50 mL) and water (25 mL) was added tetrakis(triphenylphosphine)palladium (496 mg, 0.429 mmol). The reaction mixture was refluxed for 8 hours, cooled to ambient temperature, diluted with water (200 mL), extracted twice with diethyl ether (200 mL), washed with brine, dried (Na2SO4) and concentrated to a yellow liquid. The residue was purified by silica gel chromatography (AnaLogix® SF25-40G; 50 micron silica; elution with 0-20% ethyl acetate in hexane at 30 mL/min) to provide the title compound (1.530 g, 7.37 mmol, 86% yield) as a colorless liquid. 1H NMR (300 MHz, DMSO-d6) δ ppm 8.61 (dd, J=4.6, 1.4, 1H), 8.10 (dd, J=8.2, 1.4, 1H), 7.53 (dd, J=8.3, 4.6, 1H), 6.51-6.46 (m, 1H), 6.13-6.10 (m, 1H); MS (EI) m/e 207 (M)+.

1. temperatureThe reaction mixture was refluxed for 8 hours
2. extractionextracted twice with diethyl ether (200 mL)
3. washwashed with brine
4. dry with materialdried (Na2SO4)
5. concentrationconcentrated to a yellow liquid
6. customThe residue was purified by silica gel chromatography (AnaLogix® SF25-40G; 50 micron silica; elution with 0-20% ethyl acetate in hexane at 30 mL/min)