Cesium carbonate → 5-(5-Chloropyridin-2-yl)-2,3-difluoropyridine

関与物質

反応条件

反応手順

To a pressure vessel was added 2-bromo-5-chloropyridine (3.0 g, 16 mmol), cesium carbonate (15 g, 47 mmol), 1,1′-bis(diphenylphosphino)ferrocene-palladium(ii) dichloride dichloromethane complex (2.5 g, 3.1 mmol), and 2,3-difluoro-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (4.5 g, 19 mmol) in 1,4-dioxane (120 mL) and water (22 mL). The mixture was flushed with argon, sealed and stirred at 90° C. for three hours. The mixture was concentrated, diluted with dichloromethane and washed with water. Organic extracts were concentrated and purified by MPLC (eluted with 0-10% methanol in dichloromethane) to yield 5-(5-chloropyridin-2-yl)-2,3-difluoropyridine as a yellow solid (2.4 g, 68%). MS m/z=227.2 [M+1]+. Calc'd for C10H5ClF2N2: 226.6.

情報源と証拠