[CH3:1][O:2][C:3]([C:5]1[C:6]([CH3:13])=[N:7][C:8]([Cl:12])=[CH:9][C:10]=1[CH3:11])=[O:4].[Br:14]N1C(=O)CCC1=O.CC(N=NC(C#N)(C)C)(C#N)C.C(O)(=O)C>C(Cl)(Cl)(Cl)Cl>[CH3:1][O:2][C:3]([C:5]1[C:6]([CH2:13][Br:14])=[N:7][C:8]([Cl:12])=[CH:9][C:10]=1[CH3:11])=[O:4]To a solution of 710 mg, (3.6 mmol) 6-chloro-2,4-dimethyl-pyridine-3-carboxylic acid methylester in CCl4 (16 ml) were added 688 mg (3.90 mmol) N-bromosuccinimide, 59 mg (0.36 mmol) AIBN and 210 μl (3.72 mmol) acetic acid. The reaction mixture was irradiated with a 200 W Wolfram lamp at 60° C. for 24 h. The mixture was then filtered through celite, washed with CCl4 and concentrated in vacuo. After CC (hexane/EtOAc 97:3) of the residue a mixture of 6-chloro-2,4-dimethyl-pyridine-3-carboxylic acid methylester, 4-(bromomethyl)-6-chloro-2-methyl-pyridine-3-carboxylic acid methylester and 2-(bromomethyl)-6-chloro-4-methyl-pyridine-3-carboxylic acid methylester was obtained. This mixture was dissolved in dioxane (10 ml) and added at 0° C. to a solution prepared by dissolving 594 mg (25.8 mmol) sodium in MeOH (11 ml) at 0° C. This reaction mixture was stirred at RT for 3 h. Then the reaction solution was poured into water and extracted with EtOAc. The organic layer was washed with water and brine, dried over Na2SO4 and concentrated in vacuo. After CC (hexane/EtOAc 97:3) of the residue again a mixture of 6-chloro-4-(methoxymethyl)-2-methyl-pyridine-3-carboxylic acid methylester and 6-chloro-2-(methoxymethyl)-4-methyl-pyridine-3-carboxylic acid methylester was obtained. This material was dissolved in NMP (7.8 ml) and 860 μl (9.85 mmol) morpholine and 1.36 g (9.85 mmol) K2CO3 were added followed by heating at 100° C. for 5 h. Then the mixture was poured into water and extracted with EtOAc. The organic layer was washed with water and brine, dried over Na2SO4 and concentrated in vacuo. Purification of the residue by CC (hexane/EtOAc 9:1) provided 90 mg (0.32 mmol, 9%) 2-(methoxymethyl)-4-methyl-6-morpholin-4-yl-pyridine-3-carboxylic acid methylester.
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