Cesium carbonate → 6-Cyclopropylmethoxy-5-(2-methyl-pyrrolidin-1-yl)-pyridine-2-carboxylic acid

Beteiligte Stoffe

Reaktionsschritte

Under an atmosphere of nitrogen, a solution of 5-bromo-6-(cyclopropylmethoxy)-pyridine-2-carboxylic acid (Example 9 d, 0.4 g, 1.5 mmol), 2-methylpyrrolidine (CAN 765-38-8, 188 mg, 2.2 mmol), R)-(+)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (CAN 76189-55-4, 183 mg, 0.3 mmol), tris-(dibenzylidene-acetone)dipalladium (CAN 51364-51-3, 135 mg, 0.15 mmol) and cesium carbonate (1.9 g, 6 mmol) in toluene (50 mL) was heated to 90° C. overnight. The reaction mixture was concentrated under reduced pressure. The residue was dissolved in water (10 mL) and extracted with ethyl acetate (30 mL), the pH of the aqueous layer was adjusted to 2 by addition of 1 N hydrochloric acid and the resulting mixture was extracted with ethyl acetate (3×30 mL). The combined organic extracts were washed with water and brine, dried over sodium sulfate and evaporated. The residue was purified by column chromatography (silica gel, 10 g, 50% ethyl acetate in petroleum ether) to yield the title compound (0.15 g, 36.9%) as yellow solid; MS (EI): m/e=277.2 [M+H]+.

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