Cesium carbonate → 6-Chloro-5-cyclopropyl-pyridine-2-carboxylic acid methyl ester

関与物質

反応条件

反応手順

To a mixture of palladium(II)acetate (17.9 mg, 79.8 μmol), butyl-1-adamantylphosphine (42.9 mg, 120 μmol), potassium cyclopropyltrifluoroborate (597 mg, 4.03 mmol) and cesium carbonate (3.9 g, 12.0 mmol) under an argon atmosphere was added a solution of 5-bromo-6-chloro-pyridine-2-carboxylic acid methyl ester (CAN 1214353-79-3, 1 g, 3.99 mmol) in toluene (25.2 ml) and water (2.8 mL) under an argon atmosphere. The reaction mixture was heated to 100° C. for 20 h, diluted with water (17.5 ml), poured onto 100 ml ice/brine and extracted with i-PrOAc (2×100 mL). The combined extracts were dried over sodium sulfate and concentrated in vacuo to give a yellow liquid. This crude material was purified by column chromatography (70 g SiO2, n-heptane/i-PrOAc 0-10% over 120 min) to give the title compound (497 mg, 59%) as yellow solid, MS (EI): m/e=212.0 [M+H]+.

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