C[O-].[Na+].[Cl:4][C:5]1[C:10]([OH:11])=[CH:9][CH:8]=[C:7]([Cl:12])[N:6]=1.CS(C)=O.[CH2:17]([N:19]([CH2:24][CH3:25])[C:20](=[O:23])[CH2:21]Cl)[CH3:18]>CO>[CH2:17]([N:19]([CH2:24][CH3:25])[C:20](=[O:23])[CH2:21][O:11][C:10]1[C:5]([Cl:4])=[N:6][C:7]([Cl:12])=[CH:8][CH:9]=1)[CH3:18]A solution of 4.6 g of sodium methylate (0.2 mole) in 50 ml of absolute methanol is slowly added at room temperature to 33.4 g (0.2 mole) of 2,6-dichloropyridin-3-ol. There is then added, with gentle heating, 100 to 150 ml of dimethylsulphoxide until the cloudy solution becomes clear. The solution is then heated to 80°-90° and methanol is distilled off. The reaction solution is cooled and an addition is slowly made dropwise at 0°-10° C of a solution of 60 g (0.2 mole) of chloroacetic acid diethylamide (dissolved in 300 ml of dimethylsulphoxide). After the dropwise addition is completed, the reaction mixture is stirred at room temperature for a further hour. The solvent is distilled off under reduced pressure; the oil remaining is taken up in ether, washed with water, dried and freed from solvent to leave N,N-diethyl-(2,6-dichloro-3-pyridyl)-oxy-acetic acid amide, which boils at 137°/0.4 torr; yield: 35 g (62% of theory). Treatment with ethereal hydrochloric acid yields the hydrochloride, which is recrystallised from isopropanol.
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