2,6-Dimethyl-3-pyridylamine → 4-[6-(2,6-Dimethyl-pyridin-3-ylamino)-5-methoxy-pyrimidin-4-yloxy]-piperidine-1-carboxylic acid isopropyl ester

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Reaktionsschritte

A mixture of 4-(6-chloro-5-methoxy-pyrimidin-4-yloxy)-piperidine-1-carboxylic acid isopropyl ester (1.52 g, 4.60 mmol), 2,6-dimethylpyridin-3-amine (0.562 g, 4.60 mmol), palladium acetate (0.0584 g, 0.260 mmol), and sodium 2-methylpropan-2-olate (0.663 g, 6.90 mmol) in 50 mL dioxane was stirred under reflux for 18 h. Mixture was concentrated and extracted with brine and CH2Cl2. Organic phases were dried over MgSO4, filtered, and concentrated. Residue was purified by column chromatography (AcOEt/hexane 5:1→AcOEt→AcOEt/MeOH 10:1). Fractions containing pure product were concentrated, residue was treated with 4M HCl in dioxane, and concentrated to give 4-[6-(2,6-dimethyl-pyridin-3-ylamino)-5-methoxy-pyrimidin-4-yloxy]-piperidine-1-carboxylic acid isopropyl ester as a white (0.285 g, 15%). Fractions containing product contaminated with 2,6-dimethylpyridin-3-amine was concentrated to give 0.30 g of ca 80% pure product. 1HNMR (CDCl3, 400 MHz) δ 1.24-1.25 (d, J=6.2 Hz, 6H), 1.78-1.84 (m, 2H), 2.00-2.05 (m, 2H), 2.52 (2s, 6H), 3.37-3.44 (m, 2H), 3.76-3.81 (m, 2H), 4.03 (s, 3H), 4.91-4.97 (m, 1H), 5.33-5.38 (m, 1H), 6.81 (s, 1H), 7.04-7.06 (d, J=8.2 Hz, 1H), 8.09 (s, 1H), 8.11-8.13 (d, J=8.2 Hz, 1H). Exact mass calculated for C21H29N5O4 415.22. found 416.5 (MH+).

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