2,4-Dichloroaniline → 5-Cyclopropyl-6-(2,4-dichloro-phenylamino)-pyridine-2-carboxylic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

A solution of palladium(II)acetate (4.24 mg, 18.9 μmol) and 2-(dicyclohexylphosphino) biphenyl (13.2 mg, 37.8 μmol) in dioxane (1.9 ml) under an argon atmosphere was stirred for 10 min at ambient temperature and subsequently added to a suspension of 6-chloro-5-cyclopropyl-pyridine-2-carboxylic acid methyl ester (100 mg, 472 μmol), 2,4-dichloroaniline (76.6 mg, 472 μmol) and potassium carbonate (1.31 g, 9.45 mmol) in dioxane (3.24 ml) under an argon atmosphere. The yellow suspension was heated to reflux and stirred for 20 h. The reaction mixture was poured into 20 mL ice/brine and extracted with i-PrOAc (2×50 mL). The combined organic layers were washed with ice/brine (1×50 mL), dried over sodium sulfate and concentrated in vacuo to give a brown oil. The crude product was purified by flash chromatography (silica gel, 4 g, 0% to 10% heptane/iPrOAc) to give the title compound (62 mg, 39%) as light brown liquid, MS (EI): m/e=337.2 [M+H]+.

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