[CH2:1]([O:3][C:4]([C:6]1[C:7]([Cl:14])=[N:8][C:9](Cl)=[CH:10][C:11]=1[CH3:12])=[O:5])[CH3:2].C(=O)([O-])[O-].[K+].[K+].[NH:21]1[CH2:26][CH2:25][O:24][CH2:23][CH2:22]1.O>CN(C)C=O>[CH2:1]([O:3][C:4]([C:6]1[C:7]([Cl:14])=[N:8][C:9]([N:21]2[CH2:26][CH2:25][O:24][CH2:23][CH2:22]2)=[CH:10][C:11]=1[CH3:12])=[O:5])[CH3:2]A mixture of 2,6-dichloro-4-methyl-pyridine-3-carboxylic acid ethyl ester (29.7 g, 127 mmol), potassium carbonate (26.3 g, 190 mmol), and morpholine (13.3 g, 152 mmol) in dimethylformamide (350 ml) is stirred for 18 h at 95° C. After completion of the reaction, water is added and the mixture is extracted with diethyl ether (3×). The combined organic layers are washed with water (2×) and brine (1×), dried over magnesium sulphate and evaporated to dryness. The crude product is purified by flash chromatography (silica gel, 25% ethyl acetate/cyclohexane) to yield 2-chloro-4-methyl-6-morpholin-4-yl-pyridine-3-carboxylic acid ethyl ester (10.5 g, 36.9 mmol, 29%).
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